Having been in artillery, my bias runs towards 'bigger boom'.
I'd wanted to try my hand with an H&K USP .45, but it's grip was about the same size as the Beretta's.
If I could get something in that size range, I'd probably have to work on wrist strength to be able to hold it steady.
(Not something one usually has to worry about with rifles.)
6 lbs is a bit much for a handgun without wheels. I've found stuff in the 40-45 oz range very easy to deal with.