One hitch to most of our carefully laid plans? Nature has a way to deciding what works and that decision is constantly changing! What fits and works will often be a matter of not only what we want to see but nature has a way of letting things grow and mature, which means a plant that gets the right light on a new tank may be shaded later and that means the plants may need to change. I find many things I do in my tank work the same as in the yard where it is always a chase to keep the right amount of sun loving plants versus the shade as trees and shrubs grow.
I might suggest starting with 12-15 types, find what actually wants to be in your water, with the way you maintain the tank and then move from there as you will certainly have far larger and possibly more plants as time goes on. Some will grow and multiply while others may wither and die so I work not on a pre-set plan but adapt things as I find what works. I have hard/alkaline water and others may have soft acidic water, so making a plan that works will have to have a better idea of what plants work best in YOUR water.
I find that plants in nature tend to grow in groups as they multiply, so I do favor groups over individual plants. In nature, this is often due to a variety of soil and each type has it's preferred type but in our tanks that can often be a limiting factor when we only provide one type of substrate.
Trial and error and adapt as needed?