I'll hv to disagree wif saying using cannister filter as a "sin". i myself is a user of cannister. yes, i do agree that a sump gives u better and more options. but for ppl with space constraints, using a cannister might only be the next best thing. it depends on wat u place in ur cannister. for me, i put nothing but only GAC and polyfilter. no harm done. as long as u can afford to do regular maintenance.
as for fluroscent lights, IMHO, it is not going to be enuff even for the simplest of hard corals. unless u hv a really really shallow tank or a FOWLR. i suspect that it is not going to be enuff to keep softies.
juz me 2 cents.