Don't have personal experience with Bala Sharks, but some of my favorite fish right now and maybe not in the same tank are Cardinal Tetras, German blue or yellow (long) finned Rams.
Another which is really pretty is the Black Phantom Tetras. If you can see them in person, my lfs has some and they are stunning. The pics on Google aren't very impressive btw.
If you have some good experience, another beauty is the Discus, so many gorgeous colors and patterns.
You will find something fabulous. I am putting up my new 72G this week and I can't even imagine what I would do with so much room! lol Will be following the adventure.