Longer stroke=higher piston speed=more depression (vacuum)=higher port velocity=lower peak rpm. To maintain rpm, an increase in duration or cylinder head capability is needed.
For a larger bore, same thing.
larger piston=more area=more depression (vacuum)=higher port velocity=lower peak rpm.
Again, this is assuming all else is the same except how the cubic inches are achieved. That's not saying the final cam selection might not vary between the two, but the trend is going to be the same to get the same result.