What to use - a McIntosh MC202 or a MC7300?

I would think the MC1's would be harder to drive than your center. Keep the 2 MC352's to power your front and rear and mono the 202 for your center. The MC202 would be a nicer match as it uses the newer end caps that would align with the MC352's, plus it is in the same series as the MC352.

Not sure you going to hear the difference with the larger MC7300 to power the
rears. I would go with the MC202.

I have 250 watts Musical fidelity amp on my fronts. And 100 watts on the center
and rear channel.