Hello St. Emeric, nice to have you here.
There are a few people here, who share your desires for more single player games. Unfortunately they take time to make, especially if you want an ai on the map. As a result, people are playing multiplayer, where they get intelligent opponents on their map without programming an ai.
And don't worry about your multiplayer skills. The good players who would rush you with stickyfoam lynxes while you're building a residence in a morale-steady game are no longer around. (just the ones who would send acid clouds to you at mark 120)