Hey, I missed this before! It's really cleverly constructed. (And hardly the first isometric / hex / 2.5-D tileset anyone's made -- there are several included in the default tilesets!) In fact, I played a little environmental by Variad recently, "Warmth" (
knyttlevels DL link) which included an isometric screen in an otherwise entirely-side-scrolling level, which actually worked surprisingly well.
Are you still thinking of maybe doing a hex level with it, after you finish your other level-in-progress? Also, what's your existing hex level called?