I'm in a similar boat, but I've found where I once habitually put things in the same workspace every time and was able to trivially recall them, I now end up all over the place.

Also I've been missing scratch deeply.

I'm sure it's solvable with some diligence and config changes, but I haven't invested the time yet.

This is sway on scrolling steroids:

https://github.com/dawsers/scroll

I'd agree with sph about having one workspace per activity. I've never had a rigid workflow with lots of permanent named workspaces, but I have a workspace-naming script that lets me label my numbered workspaces after they've been set up.

Other things that help include a fuzzel-based open window searcher and, to be honest, restrained use of Niri's flagship scrolling feature. Most of my workspaces most of the time are the same size as my screen, with the scroll used very sparingly for usually temporary overflow.

I guess it also helps that I never used the i3 scratchpad so I don't miss it.

I mentioned elsewhere that scrolling WMs shine when you use a workspace per activity. You should never "have stuff all over the place", you should be working on a single one until you context switch.