I just broke down my 40B so I have been through your thought process. 1st run a sump! Its the best way to keep things simple and clean. 2, a 20 gallon tank worked great. Build your own chambers to make sure you can do what you want with your tank. 3, EVERGROW lights are great. Talk to richard from ERC about it, I ran the 32" model for reference. 4, a hang on over flow is ok, some dont like them. I had one from CPR with a aqua lifter pump and it worked great. And lastly if your going to build a stand build it bigger than you need. The extra room is great!!! Just my 2 cents though, and dint forget to do a build thread.