How experienced are you as a fishkeeper?
One year or less?, 5 years?, 10 years or more?
If around one year, to 5 years, I would suggest, common, tank raised, aquarium strain angels.
With the above, small to medium mistakes are tolerated
If you have 10 years or more, then some of the more challenging type like altum, Peruvian, or leopoldi, these require much more attention to detail, like stringent water parameters, and care.
With these, one false move, like a less than drastic change in water parameters, or lack of perfect water quality, and they are all dead.
Some other minor details...
How many water changes do you expect (or have time do) per week?
This might determine what size and number of fish you keep.
A few large, adult cichlids (like oscars) might require 2 x 50% water changes per week or more, depending n your waters buffering capacity.
How often do you expect to monitor your water parameters per month?
If keeping sensitive species, this might require constant monitoring until the tank reaches equilibrium (almost a year).
Certain species prefer certain type substrates, certain species are good "or not", with plants.
There are other questions, that would determine tank stocking species and levels, but ...... not yet.