I think modern TTRPGS in general steer towards things like temporary summons because of how it lets the players actually use them in combat. Nobody wants to play the necromancer who is suddenly just some guy because there are no corpses available where the battle kicks off.
I have an enormous soft spot for narratively putting in the legwork to assemble your undead hordes, and when I’m the GM, I’m always keen to set up good moments for the necromancer to build an army, but it’s so easy for that to set up a situation where a player doesn’t get to actually use their features. Making them temporary summons from nowhere in particular is the easiest fix.
If you get around to Microscope and enjoy it, it recommend both The Quiet Year and For the Queen.
When I played Microscope, I found that the game was a little too unconstrained and it was very hard to keep things from becoming totally silly, then in the close up scenes, everyone would basically want to default to playing a super rules-light generic TTRPG, and two or three of those scenes would dominate the session. I feel that it may get better with frequent play, but that’s not really what it’s designed for. Ben Robbins, the creator is a very talented game designer and is also famous for the West Marches style of D&D play, and has made numerous GMless TTRPGs since, and I’ve only ever heard great things about them.
The Quiet Year is a game with a more constrained setting, that basically uses a map you fill in as you please and a bunch of prompts tied to playing cards to play out the 4 seasons of a small settlement moving from it’s founding to a final point where either the settlement is implied to die out, or is a fantastic springboard for a traditional TTRPG to take over. There are plenty of hacks online that move the tone from a post apocalypse feeling survival focused game to basically anything that charts a settlement for a year, including one by the creators called The deep forest which I understand to be a decolonising focused and a bit more cottagecore / cottagecore. I preferred this to Microscope mostly because of the fact that it’s prompts constrain the tone from becoming all out silly.
Finally For the Queen has been one of the best games I’ve ever discovered. I’ve played the first edition but there is a second created by the same creator, Alex Roberts, produced by Critical Role’s Darrington Press. If you’re Critical Role averse for some reason, the first edition was not tied to them at all. This game is by far the easiest to teach new players, and is the first game I’d bring to play with absolute TTRPG newbies. In my opinion it generates the best story, although rather than being solely worldbuilding, it places a primary interest on your characters and relationships to a queen figure. I find that despite this, the world’s that comes out of it are far more evocative and exciting to develop than other GMless TTRPGs, and a large part of that is the hard to hack reality that it’s just got good prompts. Despite that it’s got the most hacks of the original of anything here, as the original game is so streamlined and well playtested, which really shows while playing it.