This may sound odd coming from someone who has kept Tanganyikans exclusively for 20+ years, but if I had a tank like yours I would go with angelfish, and plant the tank heavily with jungle Vallisneria
. Angels were my first 'tropical fish love,' and I still think they are amongst the most beautiful of freshwater fishes. There is just nothing else like them.
But by all means don't go with angels purchased from the LFS. My top choice would be wild-caught Pterophyllum altum
, which are absolutely stunning. My second choice would be wild-caught P. scalare
from Peru. My third choice would be stock purchased straight from a dedicated angelfish importer/breeder, preferably F1 or F2 from wild. Any of these fishes will be so much more interesting, challenging, and yes, aggressive than domesticated angels, which have been bred in captivity for more than 100 years, and are many generations from the wild. Here is one of my favourite breeding pairs of F1 angels that I obtained by crossing a wild-caught Peruvian scalare
female with a black male, many years ago. Just stunning fishes, and someday I will keep them again. Good luck!