So having only done one playthough I can't comment on all of these, but...
2.
Why would you want to get rid of one of the coolest parts of the game? I'm fine with admitting it's too easy to get, but the 'shouldn't be a thing at all' is ludicrous to me. Single-player RPGs have a long history of allowing elemental immunity, and occasionally absorption, through equipment. Divinity just lets you build up to it instead of having to find the legendary Flame Armor or Bolt Ring. Is it too easy to build up in D:OS? Sure. But the problem is not "People can build to heal from ice" but "People can easily build to heal from all four primary elements." I'd suggest dropping overall resistance buffs by about 30%. Maybe a bit more. But I'm actively opposed to a cap. Make us work for immunity and absorption, but let us have it.
I don't like immunities because they remove tactical depth, at least in their current form. If you're immune to all elements, you are basically invincible to a lot of mobs which were meant to provide a challenge. I'm ok with having a character immune to 1 or maybe even 2 elements (see my traits suggestion) , but definitely not all. And if that's an option, AI should be smart enough not to attack you with spells that heal you, at least after the first try.
6. Clearly we have different definitions of "easy." While I've found items that give CC immunity, the're... pretty much all boots. Maybe the RNG gods just don't love me like they love you, but my character at level 20 is immune to petrification and slow, and that's it. Slipping, of course, because I'm a crafter, but other than that, I just don't have this experience at all. Never found anything that makes me immune to knockdown or stun, the two most common and most debilitating mezzes.
I've managed to find a fair amount of rings with stun/freeze immunity and armors with knockdown immunity, which seem to be most common forms of cc. Guess it's luck dependent. Overall I just think this is a bad design, since it again removes tactical depth.
III
I don't know if I'd say CC is too "easy" normally, so much as it's too swingy. I find a lot of incidental enemies just don't get CC'd no matter what we throw at them, but then, yeah, some bosses just fold like wet paper to a stun or knockdown. My suggestion would be re-checking the Bodybuilding and Willpower of various enemies to make sure they scale with how hard the foe is supposed to be, and let bosses get that -1 turn duration perk, modified so that it only applies to negative effects, not beneficial ones. And yes, Charm is /nuts./
Since the toughest enemies have about 10 willpower/bodybuilding and the fact that you can have 150% cc efficiency and debuff willpower by -12 and bodybuilding by -9 (so 270% and 240% chance respectively) I'd say they are kinda easy.
