I think (as usual) Sushi's got you covered.

My steps would be:
1. Play (a lot) with speaker placement;
2. Think very seriously about rugs/drapes and other room changes that can significantly alter your experience; and
3. Start looking at speakers that can move more air.

I don't think wall-mounting the speakers or getting a bigger amp is going to make the difference that you need.

Good luck. Please do report back with updates

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