We will find out the answer to all these questions, eventually. They are good ones, so hopefully Larian is listening if they haven’t already thought up solutions.
Personally I don’t think I’ve ever had a companion in a game that I initially liked but eventually grew tired of, but that seems like a reasonable possibility.
We know that if nothing else you will be able to add custom characters, though that isn’t a sufficient substitution for most people. Hopefully the characters are all written well enough that none of this should be an issue.
