Okay, I was messing around on YouTube 'cause I was bored, and I stumbled across these gems.
(Listed in order of epicness:)
Ready, Steady, Go
Tobira No Mukou
I instantly fell in love with these renditions of the OP/ED themes and nearly went crazy trying to figure out where they came from. I did some more digging, and apparently, there's an official FMA album with these instrumentals of all the old TV theme songs.
Did anyone else know about these? 'Cause I had NO idea they existed and it makes me mad because THESE ARE SO FREAKIN' AMAZING. I've never been really impressed with the OPs and EDs for the first series (except for "Rewrite", which we can all agree is awesome). But these tracks have put a whole new spin on them and now I've finally found a way to love them. Wow. Just...wow.
Brotherhood may pwn FMA plot-wise, but it can never hold a candle to any of its gorgeous, moving, heartfelt orchestral music IMO...whether it's this, or the OST itself.