From playing the original version, I know that the early game is awfully grindy and you have to pick-and-choose the lowest-hanging fruits to get the ball rolling, but then it can snowball pretty hard from there. There are at least six ways to escape the fort, but you probably want to do all of them for XP, which breaks immersion, but they didn't really balance around it (by awarding more XP and then evacuating people related to the other methods, for example...)

How much has this been addressed, if at all?

Was it always possible for Butter to take your side against Griff? Last time I checked, even if you charmed Butter, she still sided with Griff. I don't know whether this is new to Definitive, or if I simply hadn't attempted this since Early Access...

At any rate, it turns it from into a grueling Lvl 3 fight to a fairly hard one, given how few your chances are to power up before this point.

I still find early quest order extremely vital, but I successfully escaped the fort (not the entire island) with no serious setbacks. I'm not sure if it's because the game got easier, or if I just remembered a few tricks that make a huge difference (e.g., lure the Houndmaster out of the room and shoot from the balcony) It still feels like keeping Cork alive was a lot harder pre-Definitive Edition, though.