I've been on vacation in Mexico, and it put me in the mood to reflect on things I don't normally think about. It led to an essay in which I try to articulate why abstract games mean so much to me.
I tried to go beyond the usual "I-like-X-because-of-features-Y-and-Z" explanation. It was hard to write.
I'm curious what are your thoughts on the importance of 2 players vs 1 player, since Nurikabe, for example, has the other qualities you list, though perhaps not as much depth.