In the gym I trained at we sparred all weight classes. I sparred both amateurs and pros 3 times a week.

The guy I least liked sparring was 3 inches shorter than me and weighed 135lbs sopping wet.

His punches where brutal. Snap your head back and rattle your brain punches. I'd take a slow, heavy thud from a heavyweight any day over that.

Pushing power does matter though on the inside and in cornering someone. But half of that comes from your legs and your bodyweight.

But you don't really need more than 50lbs over your body weight. Say I'm 175 and I bench 225. I'm not going to push a 270lb guy backwards even if I could bench that. I'm going to end up just pushing myself back off him. That's ok for separation but I have no power to my punches going backwards.

Better to balance power with speed and agility so I could, instead, circle right or left quicker than he comes in straight forward on me and trail a hook on my way out.