Behold why UIs get super bloated over time. Users can want entirely different things. =)

Same. I never use spaces or apps in fullscreen (except when watching videos).

I find it way easier to do CMD + TAB to switch between apps, than having to switch between spaces until I get to where I want to be.

I use full screen when I am working just in the MacBook and no other screens attached. It’s simpler to swipe between desktops. It’s annoying when I use my external monitors.

Multiple desktops/spaces, with my mainstay apps each assigned to one desktop, fullscreened with BetterSnapTool, and helper apps like notes, terminal, calendar & mail assigned to all desktops then just swap between apps/spaces either by pressing the dock icon, by four-finger swipe (very quick if switching between adjacent spaces), or four-finger swipe up to open app expose and switch between apps or spaces. I love this setup, and whenever I'm forced to use Windows, I'm incredibly frustrated by its comparably terrible window & desktop management

cmd+tab does search across spaces though, doesn't it?

For me, it depends whether I’m using a laptop or proper size monitor.