Since you are moving up in the tank world have you considered Oscars?
They are hard to "kill" and grow quickly to the size of the tank they are usually not aggressive to tank buddies of their own kind (other oscars) as long as they grow up together. They come in a range of colors and are "social" they will eat out of your hand they come to the tank and follow you beside it. i had 3 in New Jersey. i could pet mine! I kept their tank clean, they help their too by moving the gravel where THEY want it( LOL
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I also had a placlastimous (spelling on that i have no idea) you know those black algae eaters. They also grow quickly to the size of tank and a channel cat for bottom feeding.
The Oscars used to "pout" when I cleaned the whole tank (new water etc) by laying on their sides in the bottom. you need a good filter (like a Fluval) and a sturdy heater (my oscars broke 2 heaters!). large decorations like a rock, cause plants they will pull up constantly. In between tank cleanings I used a tank vacumme to suck up the poo and gunk on the gravel, then just add some clean water back to the tank.
They don't eat much pellets if you give them feeder fish every month (they will gorge them selves on those!) and their "chocolate" treat is crawfish which we used to get from the creek bed behind the house. They like brine shrimp and are fun to watch grow and watch how they sttend to you.
We had the 3 oscars, channel and plato in a 39 gallon tank. And they all lived in harmony together.
Tip on large tanks, keep near a opening to the outside world like next to (not in front of) a window or door. it is so much easier to clean out, you just put a garden hose in it and syphon the water outside!
Best of luck
