Could you add new feature to enable swipes by holding some modifier key(s)?
For example hold Shift + Cmd + Swipe_4_fingers_down to change space.
Can't think of a technical reason why not, except I don't think I've been asked for this feature before, so not sure how much demand there is for it.
For now, I use BetterTouchTool to trigger TotalSpace keyboard shortcut by holding alt key then swipe. But, for some reason, I can't use Shift+Cmd to trigger the keyboard shortcut.