True, I find resizing and tiling specifically a 3 window screen in a 1/2, 1/4, 1/4 setup to be impossible to figure out - often I just move windows around repeatedly until I give up. If I could drag directly it would definitely make it easier. But that's relatively rare for me.

I have Super+Numpad assigned as window positioning hotkeys in XFCE. First window would be Super+4 to position it on the left half of the screen. Next two would be Super+9 and Super+3 respectively to position each in the upper-right and upper-left corners. Super+5 maximizes.

Sway actually has really good mouse support! Try dragging windows around while holding the $mod key :)

WOW! I had no idea. That's awesome, thanks for informing me :)