*throw rotten fruits at you*
Die, Summoners, die !
I know I'll be disappointed when it's Polymorpher and Summoner. Two stretch goals wasted for me! Maybe Polymorpher can be salvaged though.
I think good skilltrees should cover both non combat and combat. As much as I'd like to talk my way through the game and avoid combat, the Divinity games are essentially combat driven. Still, a little non-combat freedom would be sweet !
Somehow I don't expect a full polymorph / shapeshifting at all, or maybe as a late, endgame feature. I strongly discourage any kind of polymorphing into another race : there were already a lot of design and conceptual issues with the Mask giving the player the ability to do just that. So a human being able to polymorph into a lizard and essentially bypass some of their own racial pros and cons is a definitive no-no.
The ability to change into a target animal which in turn would enable you to speak with said animal ( as a kind of replacement for Pet Pal with more versatility ) or spy on a conversation "safely" is a little more seducing. It's lots of work though.
It's been mentionned that polymorphing into a rat to, say, enter a room through a hole was impossible, technically, as the editor wouldn't allow for things like smaller gaps. Though it could work with a contextual action "enter the hole?". Maybe it's an idea.
To be honest I don't expect Polymorphing to be that incredible. I linked Tan Burci's illustration of a woman turning her arm into some kind of steel whip, to which Swen commented "Oh, look, Polymorphism !", leading me to believe it's essentially going to be local transformations that will primarily be usable in combat. Maybe out of combat advantages like running faster, as you suggested. Acrobatics, flight, swim, I don't believe any of this is going to be in the game, unless they go the extra mile and add special interactions to the elements to react to a potential Polymorpher in the group. It would be neat, but I doubt it will happen.