For generations Reform Judaism has asked its adherents to be active and social people of character. It has called upon its followers to do good and act justly. But it hasn't asked them to perform meaningless acts of ritual that have lost meaning over time. Because of this Reform Judaism has grown and been able to expand to fit the needs of modernity.
I disagree with your statement “the idea that sacrifice having nothing to do with the elevation of our spirit is a misunderstanding of the nature of sacrifice." That is why sacrifice isn't done now and we shouldn't be working for the coming of the next Temple. The idea of the "Temple," where all people will work together and live in peace, is wonderful.
But a return to a hierarchical structure where folks with the correct linage will lead the Jewish people would make a majority of the men in your Yeshiva pretty upset. For when Steven Cohen of Fairlawn, NJ (a non-kosher non-shomer-shabbos type) comes to the Temple, he will have more access than rosh yeshiva thus destroying all of his holier than thou platform.
The act of taking on responsibility from within creates a much more personal and mature connection with tradition. By simply praying for something you want, use for example the Temple or the Messiah, and not actively pursuing it in a way that is based in the reality in which we live, is as if you are acting as a child.
So to borrow from your parent example, say you want something that your parents don't want to give you, so you sit and hope that it comes your way. You could however do something that would be pleasing to your parents to gain favor. You clean your room. You wash the dishes. You do your homework. (All of these things are logical and necessary obligations given to you by your parents.)
This will bring about two things, your work will be done and you have a better chance to get what you want. But if you don't do the actual work to fulfill some of your responsibility, then you are stuck without anything at all. Same goes with religion.
I would love to see a time when the Messiah comes and we all live in peace and such. Odds are slim. So I will work hard, by taking responsibility to make the world better. Is this selfish as you say? Sure and I don't care if it is. I want to live in a better world and I want my children to live in a better world. Period.
Will the world be a better place if I welcome the stranger and visit the sick? Yes. Will the world be better if I keep the lights off on Saturday or not use a razor during the Omer? No, I will be in the dark and hairy.
You say "God, being infinite, doesn't gain from you sacrificing anything. But in the act of sacrificing an animal the intended pyschological [sic] implication is that you are a human and are falable [sic]. You've made a mistake, a sin of some sort, and want to repent in hopes of bettering yourself." This idea is inconsistent with most accounts of reasons for sacrifices and commandments. Why are we doing anything according to rules if God is infinite and un-needing? And why are we selfishly killing an animal for our own good if not for the benefit of God?
We pray for ourselves, for our people, for the world, and for God. Prayer took the place the sacrifice and the idea of scapegoating in favor of creating a version of self-reflection and acceptance of responsibility. This was both because the Temple was destroyed and that it was a logical next step in the evolution (or reform) of Judaism. There is evidence that prayer was taking place in synagogues even before the destruction of the Second Temple.
I say we need to make educated choices of how we engage in our comandedness and how we work towards creating a better world. The idea that placing the onus of our responsibility into the blood of an animal to wash away your sins is barbaric and juvenile. Moving on and growing up past our younger states is what the Judaism I know is all about. This is why on Yom Kippor we may pray for forgiveness but only are forgiven for the sins when we apologize to those whom we have sinned against.
Now if you argue that this isn't really Judaism, then I say you are only looking at what you were told at Yeshiva and not thinking about it.