[Old Yeller 1970]

The only thing I would change would be to use something other than glasspacks. Typical glasspacks won't let your exhaust flow to it's full potential. If you want the glasspack sound with better performance the Hooker Max Flows are technically packed with fiber glass but they are some of the best flowing performance mufflers available.

Since you're going to add forced induction later you may want to go easy on the static compression ratio.
Or start with a slightly smaller cam while it's naturally aspirated and then move up to a larger one when you add the turbo/supercharger to keep the dynamic compression ratio in the correct range.

However, the best thing to do, IMO is to build it naturally aspirated and leave it that way or save until you can afford the supercharger and build it for the forced induction. If you go forced induction you'll want to get forged pistons or if you leave it naturally aspirated you can save some $ and use hypereutectic pistons. There are other considerations (ie more expense) to building a forced induction engine, that will last, when compared to naturally aspirated so be sure you count all the cost.