|I really must get around to painting Annette's figure properly.|
I like this offset-square layout for gaming on; it provides all the benefits of a hex map (which I've also got several of) while being much, much easier to draw accurate room layouts on without getting lost in counting hexes. We don't go all-out tabletop-miniatures-wargaming style, but it does reduce the chance of mutual misunderstanding when it comes to determining just who is eligible to be brutally dismembered at any given time.
I draw the layouts in dry-erase whiteboard marker. Some colours (red, for example) are a lot harder to erase without solvents than others, but I mostly just use black, so that hasn't been a big issue.