Ovinomancer
No flips for you!
I've been using Roll20 for three years now, and I positively hate the drawing tools. Having to hold down <shift> to snap to grid is totally backwards from how you have to hold down <alt> when placing an art asset to get it to NOT snap to grid. There's no fill tool, you have to plan your fill ahead, and you can't use textures. Line sizes are odd. Text sizes are odd. The way that things layer is odd (the last thing drawn is on top, so if you don't plan your placements you can occlude things easily and then have to do a merry 'pull to front/push to back' dance. God help you if you have multiple things stacked, like a floor, some walls, and a door if you accidentally get them out of order in placement!It has freehand drawing tools, too. You can absolutely treat it like a battlemat and dry-erase marker.
What part hasn't worked for you?
Gah! I like Roll20 (obviously, I'm still using it after sampling other VTTs), but the drawing part of it is not good. I make my maps in GiMP and then bring them over to R20.