Not looked at my settings for a little bit, but it looks like you've ended up with settings close to mine. I've always had real twitchy and responsive settings with no AA or deadzones and had to increase the sensitivity to try and counter the new turning issue.
In addition to what you posted, I'd like to suggest that people have a look at the presets for Wiimote setup on the Gamepad. Changing between these presets may sort the aiming issue. It may be worth a look at the "aim style" setting and testing with that.
I haven't yet found any fix for the clunky and heavy turning other than what you have also suggested. It lessens it a little but doesn't solve it completely
I think the problem with the heavy clunky turning is that sensitivity settings just improve how fast the cursor and camera respond. Camera speed makes it turn faster. So now you get this deal where the cursor moves fast, but the camera doesn't. Which to me makes it feel even weirder. That's what I got out of my 10 minutes with it the other day. I haven't tried it sense. Instead of messing with my settings to try and find a work around I've been waiting for a patch.