Mouse button combinations?

With all the advanced stuff BTT can do (trackpad gestures, etc), I do not understand why mouse button combinations are not a thing. I frequently dock my Mac while at home and it perplexes me to think that I have a mouse whose potential is going to waste by simply not being able to assign mouse button combinations. For example:

LMB + RMB = cmd+shift+] (to cycle through windows to the right)
RMB + LMB = cmd+shift+[ (to cycle through windows to the left)
MB4+scroll down = volume down
MB3+scroll up = volume up

these are just a few possible useful mouse button combinations. Will these features ever be available?

This can be done with Keyboard Maestro. Hope to see it come to btt though.