carburetor riddle

I've rebuilt and had the original two barrel carb put back on my '68 318, but there are issues I'm trying to sort out. Cold starting, I have to just depress the gas til I hear the butterfly open in the carb and the choke set, rather than flooring it. If I floor it, it floods and won't start. With the choke set, it starts after a couple of cranks, runs for 5 seconds, than starts to run really rich. When it warms up, after a couple of minutes, it cleans up and runs smoothly.

The second part is that after coasting, when I step on the gas, it will try to stall (if cold) or hesitate then go (when warm). I wondered if it's vacuum related, that the higher manifold vacuum has something to do with it.

Thanks

Peter