Well, for the difficult settings there'll be more once the game is finished, it's normal to keep only one for now.
It's said we will have full Act 1, what will entail on this still need to be seen.
About changes, you can expect any more as they progress, it's the most common thing they'll do, be it the personality of characters/companions, story, etc. For Minthara, there's no need to talk much about her, there's a megathread for her, and unless a modder really likes her I don't think anyone would change her back, etc.
I find the combat good, when I start blindly I was having hard and balanced encounters. But after so much time playing it's normal to find it easier.
As for Alfira, I don't think she would be well as a party companion since it's clear she's not a fighter at all, or even seems to have any magic to that. She's just a regular bard, and I'm more than happy if she joined as a traveling companion tbh. Sharing the nights with her and maybe songs, and who knows, more? One can always dream.
