To what degree did EGW influence the development of SDA doctrine

I.
Our first conference was at Volney in Bro. Arnold's barn. There were about
thirty-five present, all that could be collected in that part of the State. There
were hardly two agreed. Each was strenuous for his views, declaring that they
were according to the Bible. All were anxious for an opportunity to advance their
sentiments, or to preach to us. They were told that we had not
come so great a distance to hear them, but had come to teach them the truth.
Bro. Arnold held that the 1000 years of Rev. xx were in the past; and that the
144,000 were those raised at Christ's resurrection. And as we had the emblem
of our dying Lord before us, and was about to commemorate his
sufferings, Bro. A. arose and said he had no faith in what we were about to do;
that the Sacrament was a continuation of the Passover, to be observed but once
a year. These strange differences of opinion rolled a heavy weight upon me,
especially as Bro. A. spoke of the 1000 years being in the past. I knew that
he was in error, and great grief pressed my spirits; for it seemed to me that
God was dishonored. I fainted under the burden. Brethren
Bates, Chamberlain, Gurney, Edson, and my husband, prayed for me. Some
feared I was dying. But the Lord heard the prayers of his servants, and I
revived. The light of Heaven rested upon me. I was soon lost to earthly things.
My accompanying angel presented before me some of the errors of those
present, and also the truth in contrast with their errors. That these discordant
views, which they claimed to be according to the Bible, were only according to
their opinion of the Bible, and that their errors must be yielded, and they unite
upon the third angel's message. Our meeting ended victoriously. Truth gained
the victory. Spiritual Gifts. Volume 2, pp. 97-99
II.
At that time [after the 1844 disappointment] one error after another pressed
in upon us; ministers and doctors brought in new doctrines. We would search the
Scriptures with much prayer, and the Holy Spirit would bring the truth to our
minds. Sometimes whole nights would be devoted to searching the Scriptures and
earnestly asking God for guidance. Companies of devoted men and women
assembled for this purpose. The power of God would come upon me, and I was
enabled clearly to define what is truth and what is error. As the points of our
faith were thus established, our feet were placed upon a solid foundation. We
accepted the truth point by point, under the demonstration of the Holy Spirit. I
would be taken off in vision, and explanations would be given me. I was given
illustrations of heavenly things, and of the sanctuary, so that we were placed
where light was shining on us in clear, distinct rays. Selected Messages Book 3,
pp. 31, 32
III.
Let none seek to tear away the foundations of our faith,--the foundations that
were laid at the beginning of our work, by prayerful study of the Word and by
revelation . . . .Gospel Workers. 1915 ed., p. 307
IV.
At this time . . . Serious errors in doctrine and practice were cherished, and
some were ready to condemn all who would not accept their views. God revealed
these errors to me in vision and sent me to His erring children to declare them .
. . Testimonies for the Church Volume Five,
p. 655, 656

Seventh-day Adventists acknowledge the influence of Ellen White in
the definition of their doctrines, but insist that she is a light pointing
us to the Bible and not to herself as the final authority of truth.
Further, we insist that every doctrine we uphold is supported by the
Bible.