This is a great build and i'm glad to see someone encouraging people to have fun with what they have without going broke. While ill always advocate for more inches if it is the same cost there is nothing wrong with hopping up a 318.
I grew up in a family shop that built a lot of dirt track stuff while doing general repairs and street hop ups for people.
In the early eighties the 318 pickups and cars seemed so gutless that people were unhappy with a year or two old car. These were low mileage vehicles only a few years old. The recipe I learned from my grandad was simple. Cars got a low buck sealed power 340 cam. A set of 360 smog heads milled .040,three angle valve job,steel shim head gasket.(people now days seem to claim this wont work). If the customer wanted to pay a very basic gasket matching and porting. The same cast iron 340 intake manifold or an edelbrock depending what was available. Sometimes a thermoquad,sometimes a holley economaster 4 barrel and occasionally a racier piece if the customer insisted. The lean burn ignition was replaced with factory chrysler electronic and echlin ignition box.
Pickups got the same treatment with a different cam. People raved about the drastic improvement. It always seemed these mild hop ups drove far more repeat business to my grandads shop than all of the really hot dirt track,drag and street stuff that was built. But that may be my perspective as a teenager enamored with anything mechanical.