I miss TotalSpaces2 too.
Other issues mention yabai and skhd (e.g. The suffering is continues people need a cure - #6 by Mitch_Neverhood) as possible friends in this matter, and building on these amazing tools I’ve created GitHub - mikkelricky/grid-spaces: Grid.
It’s very simple, but does what I need the most: moving up/down/left/right in a grid and moving the current window up/down/left/right. Feel free to try it out.