Just save up and do it right!
Sump, In sump Skimmer, drilled Overflow, and ditch the idea of canisters. You will have better luck I guarantee it. Two K3's will be enough for FOWLR
not quite enough if you go reef. I'd go three K3s TBH.
As far as BB, it's a personally choice really. I don't mind the looks of BB on tanks and I hear it's easier to clean up. I just prefer the look more with a small bed of sand.
Are you a GIRS member??? I just seen that you are in CR.