Here's my (amatitlania sp.) honduran red point colony for example, it's only a 30 gallon, but I have 12 adults and around 30 juveniles in there. In my opinion, you get a lot more interesting behavior and subsequent entertainment from this dynamic, with all the little interactions between individuals, and the occasional pair or two starting a family in one of the corners.
Any of the cryptoheros species, or amatitlania myrnae, have the most interesting behaviors in my opinion, as the females will color up and form territories to dance for males that pass through. Here's my cryptoheros cutteri colony as well:
Thorichthys, such as firemouths, also have interesting behaviors in colonies, as when they spawn, they seem to prefer to spawn at the same time as other pairs, and the territories they form are extremely small, so you will often get 3-4 pairs spawning in a few square feet of space. The way they raise their fry is interesting as well, as once the fry get big enough and start moving around more on their own, they stop trying to sort their fry from the fry of other pairs, and just raise them together.
With all of these colonies, you don't have to worry about overpopulation if you leave the fry with the parents. With enough individuals to start, and enough space (which you have), this will make for a very entertaining tank. If you or your wife like the Honduran red points as well, I would be happy to provide them.
