Bigger valves in 302 heads?

A set of 1.88/1.60's would be great for those heads. You won't see any real valve shrouding with those, and you'll definitely see some extra flow and hp out of them. The 302's still have the smaller 318 ports, so I really don't think that going to 1.88/1.60's is going to kill your flow velocity, and the larger valves will help the flow big time on the top end.

I wouldn't go up to 2.02's though, the rest of your build is pretty mild and doesn't need the larger 2.02's. Some argue that you get valve shrouding with the 2.02's. Even with those I personally don't think its a huge issue, although it might limit the benefits of going to the 2.02's. The magnum head valve sizes, 1.92/1.62, are about as big as I'd go on a 318 unless it was a very stout build. I also think the fact that the factory 5.2 liter Magnums come with 1.92/1.62's tells you that shrouding isn't an issue with 1.88/1.60 valves.

A set of 1.88/1.60's and some gasket matching should make that a pretty nice 318.