What kind of dither fish can i get?

soon i will be getting a 90gallon aquarium for my albino tiger oscar ( he is currently 2" in my 65gal with a trinidad pleco thats about 5") the 90gal with be decorated with drift wood and rocks and a few plants and caves and i plan to stock it with 1blue acara, 1 albino tiger oscar, and 1 trinidad pleco. but i need some dither fish. i dont like silver dollars (i think they are ugly) and i would really like to put some big balas in. maybe if i bought 3 small balas now (bigger than the oscar) and put them in with my oscar they would grow up together and my oscar wouldn't bother them in the 90. but i dont know if my oscar would out grow them. my oscar is pretty peaceful and i have heard of ppl keeping oscars and balas together. could this work? if not can i have some other dither fish suggestions? thanks so much!