Noise. Bubbles. If your pump too big you might be able to dial it down with a valve on the return side. Personally, I see that as a bit of a waste.
You can do whatever you want. What I don't see here is what kind of overflow you have. full siphon with 1" pipe can easily handle 600 GPH. Mine does. No noise, either.
But there's more to it than the return pump and your sump. Overflow style, one or two drains, drain size and type, plumbing and how it's assembled etc. etc. etc.
But no. It doesn't HAVE to match - depends on what you want to do and your situation.