I don't think the beam matters much for cockpit space, but maybe more so room in between facing couches in the cabin, and rough water ride stability. Basic common sense says heavier and wider boats will ride better all other things equal.
The thing that matters to me most in cockpit size, is the distance between the bolsters and rear seat, to make sure you have enough room, because that's where we'll sit at eat our lunch and put a cooler in front of us as a table. That and storage for fenders, etc in the gunwales.
And, amazing how that differs. Like, Sunsations 32 is one of the tighter ones I've seen (with the McLeods) the Baja 33 Outlaw (although a longer boat) could store a compact car. I think there I'd rather trade that for extra cabin space or engine room.
Mark