I think this is answered, but all my 3000's I've owned have been tower ROM 1.4's.
Yes, the kickstart survives reset. You have to power off to choose again. If you have the right kickstart files, you can use other versions (3.0, 3.1, etc.) or even AMIX.
No, there is no 68000 menu. That is the 2620/2630 card that does that.
1.4 ROMs also won't work with the A3640 card- you have to have at least 2.04 ROMs for it to boot.