Thank you for the detailed reply! I've never played any of the Mork Borg games. I'll give the site a look.
It might have just been the games I tried, but I had problems with big parties when playing both Atma and Monster of the Week. The usual player-GM loop of a player suggesting something and me changing the scenario in response got a little frustrating when there were 5-6 things happening in between each player's action. In the moment I could split the party up a bit and cut between them, but that led to these long periods of downtime in between turns. I might just need more experience running these kinds of campaigns.
Games that support campaigns with large groups (6-8)
I have a pretty sizeable group of friends who like to hang out and play RPGs together. We've done a handful of games, ranging from crunchy stuff through rules-lite games. But one common theme is that our games can go pretty slow. We're a group of 7 most of the time, which means 6 players + 1 GM, which is can make stuff very slow. Iterations of D&D all suffer from this, and it gets really bad in games like Dark Heresey for us. But even tropey, free-form games like Blades in the Dark and most stuff on the Apocalypse engine feel sluggish, since they're so tightly based on the Player-GM feedback cycle.
The only types of games that I've found play quickly with a large group are the light, beer & pretzels games like Everyone Is John, Paranoia, but those don't extend well beyond 1 session. I also like the higher-stakes, longer-form RPGs where the players can shape the world at scale.
Are there games that can support both longer-term campaigns AND large groups, or am I looking for the impossible here?