When I was a relatively new rider I found trying to shift mid / late turn was distracting and I wound up upsetting my bike. I practiced setting a good speed going into a turn and staying on the throttle mid-turn so as to avoid scrubbing off too much speed. I think you'll find, as you gain more skill and confidence (in yourself and the bike) you'll enter corners a little hotter and maintain that speed without dropping RPMs, thereby avoiding this problem. This way you won't need to be in first (unless it's a really tight turn) and you're exit speed and RPMs will allow a nice smooth acceleration out of the apex.
Early on I rode the same big sweeper again and again, each time hanging off and counter-steering a little more aggressively to see what I was capable of. (In fact, every Spring I still do that to get rid of winter rust.)
You seem to be on the right track by asking these questions. I would just say don't worry too much about speed. Focus on technique and being smooth, and the speed will come without you even knowing it.