This is what I've used Pop!'s Gnome extension (https://github.com/pop-os/shell) for in the past. I don't think it'll receive much love after Cosmic is released (after all, Gnome itself is being dropped) but if it still works for whatever version of Gnome you use, it may be worth checking out.
After using FancyZones on Windows, Gnome's lack of tiling management on my ultrawide has become a bit of an annoyance for me. Unfortunately, my copy of Pop Shell broke at some point.
> no fragile plugin system
While I don't like Gnome's tendency to slow down or crash, I do very much like the plugin system. Things like GSConnect and various smaller tweaks improve my Gnome experience a lot.
I hope Cosmic does expose some kind of plugin system, though hopefully one that's not as prone to lag and crashes.