Well you're going to have to tear the whole motor apart anyway so you might as well do it right once... or else you might end up having to do it again soon... ya know?
A 331 seems like the best option to me. You'll ge a little more torque without the extra weight. You could go bigger with a 342/347 stroker but I had some oil consumption problems with my 342.
Well you'll need bigger pistons and rings togo with them but thats about it. You wou't gain much power though. The only reason I could see to do it would be if you f'ed things up inside bad or if you were putting in all forged stuff.
Definately do the suspension first... it's hard to do because everyone wants more power but its the right way to do it. CHeck into the subframe connector, k member and strut tower brace from kenny brown too. I had it, made a huge difference.
Thats what I was going to say one of the cars this month did the same thing, it cost less than $1000 i think and there was a list of everything you need. It even ran like 10.96 I think.
Have you thought about a gauge cage, takes place of the center vents and has two little vents on th sides. Has spaces for two gauges so you could add another if you want.