I have made some changes to the "latest" build of RWPaint (downloadable from its homepage) including an alternate look for the canvas. If you right-click the canvas and go to the "Window painting" popup menu, you can switch between the 2 styles. The styles are remembered separately for raster and vector layers.
The "classic" look provides most information, but it can be hard to look at. Maybe there will be a 3rd option one day.
I'll see what can be done about the 100% zoom. It should not be too difficult.
Some kind of grid would be nice, but I have to work out all the details first.