I like...
hmmmrrrr... best fish is the rosy barb. Simple. It gets to a manageable size, it is inexpensive, it is cute, it is blood red and has fascinating behavior, it swims and top speed like some kind of speed demon, (then drifts slowly foraging) it likes to play in currents, it is a schooler, and a decent tight schooler at that, AND it breeds easy, it is peaceful... There are many different sorts of it. There's green ones, red ones, clear yellow ones, clear orange ones and long finned ones. Lastly, it eats filamentous algae but ignores aquarium plants!
The silver shark (bala?) is not pointless, there is no pointless fish. The bala shark lives in schools and by the sound of it yours is alone. It likely won't exhibit natural behavior without a bunch of peers. Also it had a point in it's natural habitat somewhere on the food chain. Unfortunately this fish is now endangered in the wild. One white cloud minnow will not be interesting at all. But add 10 more and you see shoaling, males displaying, etc etc.