hmm.. looks like it will be multiple comments as it is too long.

won't reveal his existence to save someone's immortal soul?

Some of this I will have already covered in other responses, I hope it is okay if I cover it again.

I think the best place to begin is to explain what the purpose of life is and then go from there. That is, there are reasons God operates the way He does and they are directly related to why we are here on Earth. It will seem round about and I am sorry for that, I can't think of a shorter way to answer that would communicate the necessary information.

First, Gods goal for us is "to bring to pass the immortality and eternal life of man". That is we are here to gain a body (in case anyone is wondering, you have succeeded at that part) and to qualify to return to the presence of God which will allow us to become gods ourselves (Joint-Heirs with Christ). Therefore the goal is to have us obtain the same state of power and knowledge that God has and just as we do not wish to give god-like power to an AI that is then going to screw things up so too God does not wish to do the same to us.

Previous to this life we lived in the presence God being His sons and daughters and we knew, as we could see him, saw the power he had, and had sufficient understanding to know, that He was God and what was right. Even in this state of knowledge 1/3 of all of God's children fell, they rebelled against God and were cast out into Hell (for simplicities sake I will use the term Hell, it isn't entirely accurate to do so but the purpose isn't to give you a complete understanding of all the details), forever. Those of us who get born on Earth did not fall but followed what was right when we knew for a surety that it was right.

Due to the fact that we did not fall we receive bodies and even after we die will again receive our bodies to no more part from them in the resurrection. This is what is meant by immortality and it is a free gift to all.

As to eternal life it is up to us on earth to live according to what we know to be right. Not what we wish was right but what we actually know to be right. This is primarily what we will be judged on. However, with the exception of Christ no one has perfectly lived according to what they know the right things to do are. We all fail and we all know that we fail, many when they so fail try to redefine what is right so that it appears to them that they have not failed but God knows their hearts and they can not fool him, or in the end themselves. Due to this state of failure, or sin, to follow what we know to be right we become unworthy of entering back into the presence of God.

This is where Christ comes in, He is our savior and able to wipe away our sins such that we can again be clean. For this to happen requires one to be baptized in the correct manner by the correct authority. After baptism one receives the companionship of the Holy Spirit to assist in making correct decisions, however one is still mortal and fallen and thus will still err regularly and so must regularly repent and renew the covenants made to obtain forgiveness again.

To obtain eternal life one must accept baptism while still alive, or at the first available opportunity when dead. That is, it does matter when one is baptized if one has heard the gospel sufficiently to have a high degree of confidence in its validity while still alive, if not then after death is fine. Refusing to hear more with the sole purpose so as to not have a that high degree of confidence (and thus not be required to change ones behaviors) is an action that demonstrates a sufficient degree of confidence for the penalty to apply

. After baptism following the commandments is required to maintain the state of grace. Everyone will have a chance to be baptized (and the other saving ordinances) whether in life or after death, this is what most of the work in the temples is.

In the final state we can end up in a variety of places, if we obtain a perfect knowledge and then reject everything then we end up cast out with those that rebelled at the beginning. Contrary to popular opinion, this is a state that will eventually be available to everyone to choose as we will all be brought back into a state of perfect knowledge and thus will again have the opportunity to reject it. If we never even tried to do what we knew to be right but accepted and reveled in our sins then we end up in the Telestial Kingdom, which is comparable to life on Earth but perfected so as to be a heaven. If we attempted to do what was right but for a variety of reasons did not accept baptism when we had the chance then we will end up in Terrestrial Kingdom, which is pretty much what is described when people are commonly describing the christian view of heaven (being no family units but a state of great happiness). The Celestial Kingdom is where God dwells and those that obtain it have eternal life, those that obtain it and are in a married family unit obtain the state of godhood called exaltation.

From all of this it should be clear that your immortal soul, while at stake, is not in any particular danger from God not revealing Himself to you. If you are trying to do what you know to be right then you have lost nothing. If you aren't trying to do what you know to be right then revealing himself to you could very well get you cast out, which is not what God is in the business of doing. He has provided sufficient evidence to suggest His existence while not casting out those that choose to not believe in the evidence provided. More evidence will be provided in the future as things get worse in the world, but until near the end it will continue to be such that many honest people that are trying to do what is right will not have to know the truth.

Warm fuzzies may or may not be a manifestation of the Spirit. It is often described as a still small voice or a burning sensation within (not a bad burning sensation, that is probably heart burn or something). It should be in both your mind and in your heart, being thoughts and feelings. This is the primary way with which God communicates with us as it testifies of the truth and lets us know what is right. It is also easily drowned out by other emotions and feelings and easily confused with other things (uncontrollable crying, a sense of community, trances, babelling incoherently, a sense of confusion are common things mistaken for the spirit) . There are a variety of other means of communication but all of them should be accompanied by this feeling of the Spirit (angels, visions, burning bush, talking donkey, dreams are some examples from the Bible of other means of communication (if I ever have a donkey or pretty much any other animal talk to me my first reaction will be to assume I had eaten something really bad or that I was crazy and either way need to seek medical attention, but it is there))