In terms of power, the cam route would be the best way. You don't need to remove the engine, just lower the cradle enough(after some other steps) and you'll be able to take off the timing cover. I was running a 3.3 pulley on a gen 3 setup with 1.9 rockers and supporting mods. After the NIC cam swap I was able to, and still am running a 3.1 on a gen 5. So that's basically running .4 more pulley than the rockers if I still had the gen 3 on it.
In terms of other mods, I've seen guys use a new GM chain on xp setups with a raised idle, and L76 or crow 105's for springs. If you were to do the NIC cam and only raise your idle by 50rpm so you can hear the white trash idle like mine, I'd go double roller to be safe.
