My requirements... what to build?

When I comes to LA small blocks, forget the year of block = good or bad. IF you have a good one, it's as good as the next one. You can sonic test the cylinder walls of two 318's produced the same year and one may have more "meat" than the other. Luck of the draw there, but don't fret about the year. Later LA's had roller cam blocks, just a FYI