What to do Next

So after a many improvements in hardware, planting, getting new fish and a lot of research (though I still have a lot to learn) I have come to a halt. I no longer feel the urge to plant and fiddle with the plants as they are right where I want them. Neons, Mollies, and Platy's swim around the tank and I have started a slow but steady test of mixes for Co2 production (which has gone poorly so far as I need to keep up production even while i am testing) and I have decided what I am going to do. I have a total 74 cm of fish in my tank. I have used up 40 cm and now have 34 cm to use. This is a good size for me as I can keep up to eight more 4 cm fish which is the size of most schooling fish. I will also be able to fit in probably two new shrimp. The new Platy's I have I can not keep so if anybody would like them reply in the comments.