I never want to / have to wonder where any particular window is. Every app will always open on the same workspace, in the same position that I define + a scratchpad workspace for random one-offs that I keep floating. I'm only ever 1 key press away from exactly what I want. I know that ctrl+b gets me my browser, ctrl+t gets me to my terminal(s), etc. I don't even think about the workspace numbers or layout beyond initial configuration. Zero animations, instant switching.

In your example, if I'm on one workspace working and I need to open Gimp, I press my keybind for Gimp and it opens on the scratchpad and switches to it immediately.

It takes a lot of initial config and tweaking as you go along but once settled it's the most efficient way I've found to manage windows, in that, the windows manage themselves i no longer have to think about them at all.

I use Awesome Window Manager and one feature I like about it is this:

Say I've got my terminal in workspace 1, Firefox in workspace 2, and Emacs in workspace 3. There are often times I need to use either the terminal or Emacs (or both) while viewing a website. So with a keystroke, I can tell it to combine any two or three workspaces and all the windows are shown tiled together. In a sense, it creates a new temporary workspace with all 3 windows. As soon as I leave this workspace, it restores it to the original configuration. No need to move windows from one workspace to another and remember to move them back.

This is the one feature that I'm really missing from Mac OS.