Just a cheap shot in the dark, but is it possible that the Ody has its own sub amp separate from the head unit?Adding an amp that small really wont make that much difference. You would need a bit more power to realize the difference.
The neoprene adds elastomeric properties to the door skin if bonded with good compatible 3m spray adhesive. It’s much more difficult to install than any matting but the performance is unmatched. I used neoprene because mold mildew and moisture can’t penetrate it. Rather than just a foam pad. It’ll stink after it gets filth and moisture in it.
I always look for drivers with very high sensitivity for the size and type in its class. Your alpines were LOW efficiency.