I take Kate's point that a lot of this has been thrashed out at the start of the 365 service but we haven't seen what might happen and so are concerned.

hseiken stresses the worth of Xara's rendering engine's responsiveness, which I fully endorse.

At the same time, I am not after vector bloat in asking but I would love to see directional lines actually having a terminal point at the tip of a head or a tail and not at the line end points; more like the Quick Shape Line, which lacks a head or tail.
Quick Shapes are naff because they do not snap to anything: c.f., dark matter and our universe.
More on lines, would be to actually snap to the boundary of the shape and not the limited Snap to Objects. Once that happens aim for sticking to a touched shape.

Acorn