My quick comparison between stock Android on the Pixel and OneUI on the Galaxy.
Pixel UI everything seems extra large or big. It's a very artsy bubbly almost goofy / funky design throughout the UI. The animations and the way things bounce and cool things like that are really neat. Which I've always liked and thought was a fun design, but I will say it's almost gotten too much into the cute almost kiddy style with things blown up extra large and silly looking at times.
Samsung's UI seems more business like, more like a Windows PC desktop UI if that makes sense? Or kind of like iOS design in some ways, and not at all the funky artsy Pixel UI. I like this newer OneUI no complaints.
The Lagwiz / Touchjizz days of old, I can officially say are over LOL. This S24 Ultra is super fast, very fluid, no lag or hiccups yet whatsoever. It's a very smooth operating smartphone to use so far.
Yeah there are some widgets or things I like better on the Pixel, wish I could get the bubbly looking Google Weather widget on OneUI, or the At A Glance widget. But I haven't dived into customization fully yet.
Ok that's my quick review after 12 hours so far.