Im all for plants. i think they're a great addition and i'm loving what your doing.
For a light or moderate bioload they can undoubtedly work wonders.
For the guys with aro's tig's rtc's or even large cichlids etc, and those regularly feeding live or frozen, i think u'll need a helluva lot of plants to eat up that nitrogenous waste.
I also think plants wont be as fast at securing nitrogenous waste as a tank turning over 3x or 4x with a healthy aerated bb colony.
With all the transpiration going on, I'd also think that u'd need to top off the tank pretty often and may often get than annoying gap between the hood and the water level.
U know the one!
Plants will be a great addition to many tanks, but unless ur gonna have a massive planted sump, u wont be able to rely on them for sole filtration.
Imagine feeding the potted pothos plant (however many u may have) silversides, mussels and massivore and expecting them to absorb all that (a crude comparison i know) ?!?!