This discussion is all very interesting, as I've only seen what a few other gamers do to cover their tables. I've always been too cheap to spring for the commercial products. So I just covered my table with old blanket material, which I spray-painted in a few colors and sprinkled with some flock and sand for texture. I can stuff old towels or rags under it to create most any shaped hills, and the material is soft enough to result in hills with soft, realistic contours. The paint hardened the top of the material enough that my single-figure skirmishers and officers stay standing up reasonably well (though most of my figures are based). My roads and rivers are mostly old cardboard and plastic sheet, painted. With decent trees, fences, and structures (also mostly scratch-built from card and natural materials from the great outdoors) one can make a pretty good looking battlefield without having to invest very much (other than time!).
Nice idea using the marker pen and stencil, I had a couple of old GW mats which were great and had many a diorama set up on them in the eighties. I like Hexons trench system and gun emplacement tiles so they have the ability to do special tiles so I live in hope of a nice embedded river system.
thanks for your opinion on hexon 2 I was hesitant but then I saw it at a games show here in the UK and was very impressed with it.