What fish should i get for my 29g freshwater aquarium?

I have had the tank for almost 3 yrs now and i am looking to get some fish that are interesting. I have a rainbow shark, pictus catfish, blackskirt tetra(which I am thinking about removing), austalian rainbow, 2 blue gouramis, and a gold gourami. I just got the gouramis a few days ago, the other four have been together for about 2 years now. After i got down to just four fish left i decided it was time to get some more. I'll probably get a couple more gouramis. I'm interested in roseline sharks, german blue rams, preacox rainbows, and maybe some sort of loaches. please let me know your opinions on which ones i should or should not get. Thanks