yeah, 2 batts and the optima will be better then good for the power
well if you want lows, make a slightly big then spec box, and tune it from 30-32hz, using a big port, and you will hit the LOWS nice... regardless of the size of the subs, don't get me wrong, the bigger subs will have more authority on the lows, but the Lows will still sound very good.
Next thing, don't get those pionners... PERIOD
lastly, get a price quote from rusty, and post it, then we can give you better advice...
if the lvl 2, are right around the same price as the cvr, i might do the lvl2's to see what there like, but the CVR 15's are proven.
how much power you looking to run just to the subs?