I guess I just don't find D:OS is really all that much about immersion in the way that Skyrim or The Witcher 3 are. Sure, obviously I don't want it to feel like I'm just playing a game, but running around the world isn't going to be immersive like it is in first or even third-person games. It's just not the kind of game where the world feels huge and epic. Maybe later in the game I'll feel like I'm deep in the wilds or trapped in a dungeon, but it's hard to get that feeling when you can just move your camera over to civilization. I don't think run speed will affect that feeling, but I guess we'll just agree to disagree. I really want quite a modest change. Many people are going to be sad about always available rift travel being gone, though I think that's overall a good thing.
I think you'll find little support for the idea that non-combat healing should take resources. You don't even need to really invest in a healer since you could just Migo's Ring (even just equipping it out of combat). Or one point in hydrosophist and restoration isn't asking much, which will be plenty of healing out of combat. Again, D:OS isn't the kind of game where you're going extremely far into dungeons and wilds and need to be self-sufficient for long periods of time. It's more about density of interesting interactions than epic immersion, at least to me.
You don't feel D:OS is really about immersion because it's all done so poorly, but it is a game that should be immersive, don't let Larian's broken systems convince you that D:OS shouldn't be an immersive game. (It is literally a role playing game, and immersion is what puts you into a role and makes you play the game in that role.)
Please, don't use examples of broken things from the game to prove a point. Yes, Migo's ring eliminates the need for a dedicated healer, eliminates the cost and reward of having one, and shitty skill trees don't force a character to be a dedicated healer. That's because these are broken mechanics not doing what they should, it doesn't prove anything other than that immersion can be done wrong, and I've already stated this.
Almost every mechanic in Divinity created for immersion is done wrong, because Larian doesn't understand that these are immersion mechanics, and throws them in without thought. If you want to use examples to prove your points, then use complete games like D&D, not broken ones in alpha.
Sorry if this all comes off a little harsh. I'm not trying to be mean or anything, text just has a way of looking angry when you're stating points.