Nice start, here's what I'd do...
1) make sure rock formations are stable
2) add a background - it will minimize algae growth, a real concern w/ the tank's proximity to the window
3) research, research, research to figure out what you want in terms of cichlids - either see what's available in your area and look those up, or pick a continent, if not a particular lake or river and research that, and figure out what could go together with out seriously outgrowing your tank
4) (personal preferences here) quit buying plastic plants and get some decent lighting, grow real plants instead - it can be a challenge w/ many cichlid species, but some plants really root themselves well, others can be tied to rocks... real plants > plastic ones