Often, former Adventists are accused on being bitter and leaving the church for emotional reasons. Below are the list of SDA official beliefs from their website. I only copied in full the doctrines that formers disagree with because they are against historic and biblical Christianity. I have highlighted the heterodox doctrines in bold and some in red.
Here is the preface of the SDA 28 fundamental beliefs:
Seventh-day Adventists accept the Bible as their only creed and hold certain fundamental beliefs to be the teaching of the Holy Scriptures. These beliefs, as set forth here, constitute the church's understanding and expression of the teaching of Scripture. Revision of these statements may be expected at a General Conference session when the church is led by the Holy Spirit to a fuller understanding of Bible truth or finds better language in which to express the teachings of God's Holy Word.
1. Holy Scriptures
The Holy Scriptures are the infallible revelation of His will.
There is one God: Father, Son, and Holy Spirit, a unity of three co-eternal Persons.
God the eternal Son became incarnate in Jesus Christ. ... Forever truly God, He became also truly man, Jesus the Christ. He was conceived of the Holy Spirit and born of the virgin Mary. ... He suffered and died voluntarily on the cross for our sins and in our place, was raised from the dead, and ascended to minister in the heavenly sanctuary in our behalf.
5. Holy Spirit
6. Creation: (Fundamentalism with a literal six-day creation.)
... In six days the Lord made "the heaven and the earth" and all living things upon the earth, and rested on the seventh day of that first week. Thus He established the Sabbath as a perpetual memorial of His completed creative work.
7. Nature of Man
8. Great Controversy:
All humanity is now involved in a great controversy between Christ and Satan regarding the character of God, His law, and His sovereignty over the universe.
9. Life, Death, and Resurrection of Christ
10. Experience of Salvation
11. Growing in Christ
13. Remnant and Its Mission:
The universal church is composed of all who truly believe in Christ, but in the last days, a time of widespread apostasy, a remnant has been called out to keep the commandments of God and the faith of Jesus. This remnant announces the arrival of the judgment hour, proclaims salvation through Christ, and heralds the approach of His second advent. This proclamation is symbolized by the three angels of Revelation 14; it coincides with the work of judgment in heaven and results in a work of repentance and reform on earth. Every believer is called to have a personal part in this worldwide witness. (Rev. 12:17; 14:6-12; 18:1-4; 2 Cor. 5:10; Jude 3, 14; 1 Peter 1:16-19; 2 Peter 3:10-14; Rev. 21:1-14.)
14. Unity in the Body of Christ
... Baptism is a symbol of our union with Christ, the forgiveness of our sins, and our reception of the Holy Spirit. It is by immersion in water and is contingent on an affirmation of faith in Jesus and evidence of repentance of sin. It follows instruction in the Holy Scriptures and acceptance of their teachings.
16. Lord's Supper:
The Lord's Supper is a participation in the emblems of the body and blood of Jesus as an expression of faith in Him, our Lord and Saviour. ...The communion service is open to all believing Christians.
17. Spiritual Gifts and Ministries
18. The Gift of Prophecy:
One of the gifts of the Holy Spirit is prophecy. This gift is an identifying mark of the remnant church and was manifested in the ministry of Ellen. G. White . As the Lord's messenger, her writings are a continuing and authoritative source of truth which provide for the church comfort, guidance, instruction, and correction. They also make clear that the Bible is the standard by which all teaching and experience must be tested. (Joel 2:28, 29; Acts 2:14-21; Heb. 1:1-3; Rev. 12:17; 19:10.)
19. Law of God:
The great principles of God's law are embodied in the Ten Commandments and exemplified in the life of Christ. They express God's love, will, and purposes concerning human conduct and relationships and are binding upon all people in every age. These precepts are the basis of God's covenant with His people and the standard in God's judgment. Through the agency of the Holy Spirit they point out sin and awaken a sense of need for a Saviour. Salvation is all of grace and not of works, but its fruitage is obedience to the Commandments. This obedience develops Christian character and results in a sense of well-being. It is an evidence of our love for the Lord and our concern for our fellow men. The obedience of faith demonstrates the power of Christ to transform lives, and therefore strengthens Christian witness. (Ex. 20:1-17; Ps. 40:7, 8; Matt. 22:36-40; Deut. 28:1-14; Matt. 5:17-20; Heb. 8:8-10; John 15:7-10; Eph. 2:8-10; 1 John 5:3; Rom. 8:3, 4; Ps. 19:7-14.)
The beneficent Creator, after the six days of Creation, rested on the seventh day and instituted the Sabbath for all people as a memorial of Creation. The fourth commandment of God's unchangeable law requires the observance of this seventh-day Sabbath as the day of rest, worship, and ministry in harmony with the teaching and practice of Jesus, the Lord of the Sabbath. The Sabbath is a day of delightful communion with God and one another. It is a symbol of our redemption in Christ, a sign of our sanctification, a token of our allegiance, and a foretaste of our eternal future in God's kingdom. The Sabbath is God's perpetual sign of His eternal covenant between Him and His people. Joyful observance of this holy time from evening to evening, sunset to sunset, is a celebration of God's creative and redemptive acts. (Gen. 2:1-3; Ex. 20:8-11; Luke 4:16; Isa. 56:5, 6; 58:13, 14; Matt. 12:1-12; Ex. 31:13-17; Eze. 20:12, 20; Deut. 5:12-15; Heb. 4:1-11; Lev. 23:32; Mark 1:32.)
22. Christian Behavior:
We are called to be a godly people who think, feel, and act in harmony with the principles of heaven. For the Spirit to recreate in us the character of our Lord we involve ourselves only in those things which will produce Christlike purity, health, and joy in our lives. This means that our amusement and entertainment should meet the highest standards of Christian taste and beauty. While recognizing cultural differences, our dress is to be simple, modest, and neat, befitting those whose true beauty does not consist of outward adornment but in the imperishable ornament of a gentle and quiet spirit. It also means that because our bodies are the temples of the Holy Spirit, we are to care for them intelligently. Along with adequate exercise and rest, we are to adopt the most healthful diet possible and abstain from the unclean foods identified in the Scriptures. Since alcoholic beverages, tobacco, and the irresponsible use of drugs and narcotics are harmful to our bodies, we are to abstain from them as well. Instead, we are to engage in whatever brings our thoughts and bodies into the discipline of Christ, who desires our wholesomeness, joy, and goodness. (Rom. 12:1, 2; 1 John 2:6; Eph. 5:1-21; Phil. 4:8; 2 Cor. 10:5; 6:14-7:1; 1 Peter 3:1-4; 1 Cor. 6:19, 20; 10:31; Lev. 11:1-47; 3 John 2.)
23. Marriage and the Family
24. Christ's Ministry in the Heavenly Sanctuary:
There is a sanctuary in heaven, the true tabernacle which the Lord set up and not man. In it Christ ministers on our behalf, making available to believers the benefits of His atoning sacrifice offered once for all on the cross. He was inaugurated as our great High Priest and began His intercessory ministry at the time of His ascension. In 1844, at the end of the prophetic period of 2300 days, He entered the second and last phase of His atoning ministry. It is a work of investigative judgment which is part of the ultimate disposition of all sin, typified by the cleansing of the ancient Hebrew sanctuary on the Day of Atonement. In that typical service the sanctuary was cleansed with the blood of animal sacrifices, but the heavenly things are purified with the perfect sacrifice of the blood of Jesus. The investigative judgment reveals to heavenly intelligences who among the dead are asleep in Christ and therefore, in Him, are deemed worthy to have part in the first resurrection. It also makes manifest who among the living are abiding in Christ, keeping the commandments of God and the faith of Jesus, and in Him, therefore, are ready for translation into His everlasting kingdom. This judgment vindicates the justice of God in saving those who believe in Jesus. It declares that those who have remained loyal to God shall receive the kingdom. The completion of this ministry of Christ will mark the close of human probation before the Second Advent. (Heb. 8:1-5; 4:14-16; 9:11-28; 10:19-22; 1:3; 2:16, 17; Dan. 7:9-27; 8:13, 14; 9:24-27; Num. 14:34; Eze. 4:6; Lev. 16; Rev. 14:6, 7; 20:12; 14:12; 22:12.)
25. Second Coming of Christ
26. Death and Resurrection:
The wages of sin is death. But God, who alone is immortal, will grant eternal life to His redeemed. Until that day death is an unconscious state for all people. When Christ, who is our life, appears, the resurrected righteous and the living righteous will be glorified and caught up to meet their Lord. The second resurrection, the resurrection of the unrighteous, will take place a thousand years later. (Rom. 6:23; 1 Tim. 6:15, 16; Eccl. 9:5, 6; Ps. 146:3, 4; John 11:11-14; Col. 3:4; 1 Cor. 15:51-54; 1 Thess. 4:13-17; John 5:28, 29; Rev. 20:1-10.)
27. Millennium and the End of Sin:
The millennium is the thousand-year reign of Christ with His saints in heaven between the first and second resurrections. During this time the wicked dead will be judged; the earth will be utterly desolate, without living human inhabitants, but occupied by Satan and his angels. At its close Christ with His saints and the Holy City will descend from heaven to earth. The unrighteous dead will then be resurrected, and with Satan and his angels will surround the city; but fire from God will consume them and cleanse the earth. The universe will thus be freed of sin and sinners forever. (Rev. 20; 1 Cor. 6:2, 3; Jer. 4:23-26; Rev. 21:1-5; Mal. 4:1; Eze. 28:18, 19.)
28. New Earth