So what do we do? Look to Narlen Darkwalk! Design NPC encounters where they do not necessarily fall under party control, but yet will participate in adventures with your character. Isn't that the ultimate single-player goal, to not need a "party" at all?
The problem in my opinion is the AI which often has less "I" in it than desired.
I like party games. I always want to roleplay one person, but that does not mean that I want to play only one class per playthrough. For me the party of 4 is the best compromise. I get some interactions with companions and I can (as meta) play several classes at once without having to play several campaigns (which I don't like). Four party members are manageable. One of the many aspects I didn't like in P:WotR (or PoE 2) was the need to play so many (in case of Pathfinder bloated and overcomplicated) classes.
What interests me not at all is playing as an origin character, for me it's wasted time on the side of Larian.
