Fog, I suspect that you'll be disappointed if you expect that a relatively modest increase in amplifier power is going to result in the sort of sound level that you described. Keep in mind that the power required for a higher sound level increases logarithmically, not linearly(e.g., a doubling of power input increases the sound level only 3dB).
Also, you're certainly correct that part of the problem is the speakers; speakers can only play to a certain loudness level before they run into volume compression and can't play any louder regardless of how much power is available. You may be at that point now with the relatively small speakers that you're using, and Algonquins, although improving the sound quality may make little difference in quantity. The only Axioms that might come close to hitting that volume level would be the M80s. So yes, I'm suggesting that your present proposal isn't realistic.
