Simple things (in no particular order) :

(1) One click to break a line (Add node - break at point - doesn't work that great at 4 am when you are tired...)
(2) Customizable stroke shapes
(3) Smooth line tool ala' illustrator
(4) Mesh fill tool
(5) Adjustable anti aliasing for vectors - fonts - bitmaps
(6) Love the Xara X capability of being able to push a line segment with the curve tool. However, having the ability to somehow adjust how the line is effected would be sweet. E.g. pushed with a sharp triangle - or circle
(7) Having a shortcut that releases (deselects) the line right away after it has been drawn. This would enable you to sketch better with your tablet... or mouse.
(8) Being able to adjust the smoothness of a line after each node you continue drawing from.
(9) Being able to customize the string of text shown, when navigating fonts
(10) Customizable shortcuts
(11) Being able to adjust hue, saturation etc. universally on all fills and lines
(12) Being able to set up your own little drawer of stroke shapes, with defined stroke weights (even better in combination with (2))
(13) Own drawers where you can drag and drop in your own shapes (and group of shapes) for later use... load a drawer - then just drag from it.
(14) I would love to see a smart drawing tool that can create a shape from intersecting lines E.g. you draw a sloppy "A" - select the lines push a button and you get the triangle part as a fillable shape... Don't know if something like that can be done... but hey, one can dream, eh?
(15) Tracer should be able to create an output of just lines
(16) More accurate Illustrator export
(17) Photoshop plug-ins compatibility up to date