I believe that God has revealed Himself through Scripture and the fullest revelation of God is in His Son Jesus Christ.
We have to be careful about what we believe is "revealed" as too often it is not what Scripture speaks of in detail or context but what we want to know. Too often we can encounter Christian "cultists" who claim that their view has been revealed to them by God, yet what is supposedly revealed is often focused on ideas about God's intention, ways, and mind rather than what is truly revealed in Scripture. Cults are no less dangerous (perhaps more dangerous even) when they are themed on Scripture.
For example, I am a Calvinist. To reference Spurgeon, I have a disposition to think of things in certain ways (if God did not change me, I don't think I'd have changed myself). But, again referencing Spurgeon, this is my understanding of what God has revealed and is prone to the limitations of the finite human mind.
Scripture does tell us that the Spirit unveils what has been revealed, but this is in association to sanctification and becoming more like Christ in our actions (evangelism, interactions among brethern,etc.).
So I'd answer the OP as "No" and "No". Sometimes Christians share their understanding which is more than just notions. We have to look at what fruit is produced, and we have to remember that often it is their understanding. But I strongly oppose the idea of a second special revelation.
What is revealed is revealed IN SCRIPTURE. Our ideas about the hypostatic union, the kenosis, etc. includes philosophical ideas and is our understanding (the varying definitions of "person" and such). BUT the Trinity is Biblical in that Scripture affirms God is Father, Son, and Spirit.
The simple way to test it out is to read Scripture (instead of commentaries). Systematically see what is said, and then see what you have.
I think that often times the answer can be seen in what is denied. The example of the OP is in regards to the Trinity. One does not have to affirm the Trinitarian doctrine to be saved (there is a lot of human understanding woven in later established explanations). BUT if one were to deny that the Father, Son, or Spirit were One God then there is an issue of denying Scripture.
That is why Scripture - not our understanding of it - is the key. Scripture is objective. Our understanding is subjective.
If anyone says "God led me to the truth of Calvinism...or Arminianism....or Mormonism (I've heard all three)" then you know to back away and hating even the garment polluted by their flesh.