I would go with the smaller cam and yes I would expect a nice gain in low speed TQ.

The computer should be no issue without a tune even(though a tuner should be able to find some more power). At part throttle it can adjust the fuel trim, at WOT (no fuel trim happens at WOT) the stock computer is soooo rich it will actually be close to just right now with the extra air flowing in the engine.

If thats still not enough I got a fresh 410 stroker I am fixing to sell that pulls like a monster.