I need to do more in game testing to see how convenient it is - I also haven't tested while I also have focus-follows-mouse turned on, so need to see how those 2 play together.

But don't do windows+1 3 times to get to window 3 - use windows+3 to get to widow 3. Open your clients in a fresh virtual desktop so you have them each in 1-5 order on your taskbar. There's no preview when switching to a numbered tab - that's the difference between alt+tab, alt+esc and windows+number