I personally would do CO2, just a diy unit, as you will have some algae growth, unless you have some good growth plants. If you have a good substrate, that much light, co2 and canister filter and good quality ferts, the only thing I can recommend for a plant is that you get a book and look through it. What some people like others don't, and it is difficult to tell ya what you like. If you give some guidelines such as height, color, leaf type, growth rates, then we can point you in the right direction.