10.2 : 1 compression 360 at sea level. Options?

Before you put holes in the butterflies, you should check the stop screw on the secondary side, and adjust that. YOur cam is not so radical that I would think you need more air. (I would 'guess' less with that size carb on this engine....but that is just a guess.) That stop being misadjusted (and exposing the incorrect amount of secondary transition slot) is a good spot to have this kind of progression/transition problem. If the idle mixture screws are not as responsive as they should be, then that is another clue to that being the issue.

And the accelerator pump cams can be changed to bring in more or less accel pump action, earlier or later.