Seems like you're replying on slipping the clutch way too much- and coasting round a bend with the clutch right in is a definite no no. It sounds like you just need more confidence riding. First gear should only really be needed for pulling away and really tight turns (U-turns). I find on my er6 that first is so low that if I go from 2nd to first at anything above about walking pace that when I let the clutch out it's like throwing the brakes on.
For the sort of corner you describe, you should be able to roll through it in 2nd with minimal throttle but the clutch out. If you need practice, find a closed Tesco car park or something and just do a few laps heading up to a 90 degree bend, slowing up, getting the right gear and then committing to the turn and seeing it through. Lots of room to go a bit wide if you don't feel it to start with.