I'll be honest, I don't think Space Age was all that good as an expansion. The developers really focused on giving the player new types of logistics challenges to solve, but that was never what I wanted. I wanted the same Factorio gameplay, but with more stuff to build. So out of the four new planets, the only one I actually enjoyed building on was Vulcanus (because it plays pretty much like vanilla Factorio but with new recipes). The lead dev is also well known for disliking logistics bots and wishes they had never been added to the game. And the expansion shows that, with (again) three of the four planets having mechanics to make use of bots more difficult if not outright impossible (Aquilo).

All in all, the developers have a very different vision of what makes the game fun than I do, and that meant the expansion wasn't much fun for me. If I play the game more in the future, I'll probably do so with the expansion disabled.