What kind of 34 footer? Most modern 34s (say Catalina) will out-maneuver the BC cutter by a huge amount. It'll be like getting out of a 67 Pontiac wagon and into a GoKart.
If you're thinking of another full keel/heavy displacement 34 footer, then you've got more momentum, and probably/possibly no improvment in close quarters maneuverability, just a heavier similar boat.
If indeed you are going to a more modern design you will be amazed at the difference, esp in reverse.
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)
1984 Fast/Nicholson 345 "FastForward"