I haven't done the longer climb you mention but have done the other two (plus others around Whitewater Wall). I found the sea washed granite to have quite a few flared/rounded cracks. I took hexes but probably only take them if you know how to fiddle them. Otherwise cams will be more useful.
As for cleaning gear, to offer something a ilttle more productive, maybe just wash them in warm water and allow to dry thoroughly before a bit of cam lube on the cams.
The drive into freycinet can be a bit brutal on low clearance cars. We resorted to having me run alongside the festiva hire car for most of the way in to pick the best line. Kinda like slalom??!! The campsite area is beautifully located. Access couldn't get much better - kinda like Point perp but not as big and can be accessed by walking down to most areas. Stunning place. Envious.