I've just taken a look at the Snap dialog. One improvement that could be made is to move the "Snap sensitivity" line to the left so it starts to the left of the check boxes. As it appears now, it seems to be an option under the "Snap to object nodes/Snap nodes to Grid/Snap points to guides" lines. This would also clearly separate the "Always Snap" lines which are fundamentally different from the other lines.
Also, it is not clear that their are two separate sections under "Object Snapping", that is what is to be snapped and what is to be snapped to, both of which must have a box checked for object snapping to work.
What about a grid (maybe with a common sensitivity setting for simplicity)?
Snap: Sensitivity Always Bounding Box Node Snap to: Path x 50 x Node x x 0.4 Grid 1.0 Guide 1.0
BTW, why is it "Snap ->nodes<- to grid" but "Snap ->points<- to guides"?
Tav