Not reform of the religion, the religion is fine. We're waiting for the rectification of the sins that keep us in exile: more unity, return to Jewish Law, etc.
With regards to the continuation of prophecy, it would be nice, but I don't really see it as necessary. We already have all the information. We know what we're supposed to do be doing. We know what we're supposed to expect, to a large extent. It's just a question of getting enough people to do it. That's not something that our prophets have historically been successful with anyway. So although it would be nice to have prophets, especially as they represent that we have a certain degree of closeness with G-d, in terms of their usefulness to the religion as a whole, there's not really much to be gained anymore. And of course, the proof is in the pudding as G-d also stopped the chain pf prophecy after that time period.
I think you are overplaying by far, the number of Jews who believed him to be the Messiah. Rabbi Schneerson was the Grand Rabbi of one Hassidic sect among many Hassidic sects. That sect may be one of the largest or perhaps even the largest of all Hassidic sects, but it does not make up the majority of Hassidim at all. And Hassidism is only of group among Ultra-Orthodox which is one group among Orthodox. So overall, we're talking about a fairly small percentage who believed him to be the Messiah. Even within his sect, not all believed him to be the Messiah and that is even more true after he died, as dying is one of the ways you get out of the Messiah candidacy list.