a center channel isn't suppose to match the other channels....it's there for fill, nothing more
don't set the gain the same as the others, set it where it NEEDS to be. Meaning, set it where it doesn't clip.
There are NO powerful center channel speakers period, much less for a single din space.
Maybe you need to read up some more on 5.1 before you go much further, it's more of an art than a bruit force....lol