All in all? 757 w/RR engines. High thrust to weight AND amazing combination of flying (Andes, Rocky Mountains, trans Atlantic, etc). IMO nothing beats rocketing out of a mountain valley in a 757, with a engine out profile loaded ("thrust, don't fail me now!")
Nicest? 777. It does so many things that make the job better.
737NG and A300 for the nicest 'balanced' airliners for hand flying. You just had to get over the 'old' cockpit crap.
Military 'nice' aircraft stopped at the T-38, which was pretty nice. Nothing like having it 'talk' to you coming around the final turn.