1. Proper spacing with the fans. 2B in particular stuffs out a lot of airdash attempts, though your best bet is to not allow the opponent to airdash at all, which I do with j.B and 5C.
2. Depending on the distance, either use your fans or just dash away if the roll puts him in throw range. The former will either snuff out an attack done/force them to block, the later puts you back in Yukiko's comfort zone.
3. Honestly, this is something I don't quite implement well yet. I tend to sit on a lot of meter that I could be using on Agidyne, so for now I just stock up to use for EX Maragi and Maragidyne once awakened.
As a Yukiko player, I wish this was all as ridiculously easy as you're making it sound.