You'll find (at least) two opinions on whether hardened seats are actually needed. One says "always", another says "only if the engine sees sustained high load, like trailer towing." I tend to be in the latter camp but don't have cold hard proof one way or the other. I know Jim Lehart tends to say the same thing, and personally I trust him on that.
As far as other work goes, with 62's and those 72 cc (nominal - measure them) you'll need to run dished pistons to get compression down in a range where it'll be comfy on 93 octane especially with a mild/stock cam. Compression ratio is another topic that tends to generate passionate and varying opinions. Can you push the limit successfully? Some people do and get away with it - but you have to really know what you're doing. For me, when I 'ran the numbers' on my engine (461) the difference between 9.5:1 and 10:1 was only about 8 hp, so I decided it wasn't worth the risk.