Have any preferences for bottom fish? Maybe Striata Botia Loach or Yoyo Loach (Botia lohachata)
Others could be
Apistogramma agassizi or Dwarf Cockatoo Cichlid (Apistogramma cacatuoides)
Green Kubotai Rasbora (Rasbora kubotai) They hang out around the top of the tank, A favorite of mine. Fast fish always moving around.
Zebra Danio or Gold Ring Burmese Danio (Danio tinwini)
Silver Dollar group only if upgrading in the future a year maybe.