I like the idea of spacing between tiles to make room for features. It's a good one. I did something similar with the tile set I uploaded, but only with exterior walls. I didn't think to extend it between the actual grid. Something for me to think about.
Looking at your example I'm a little concerned about stability. Not seeing much to hold those walls up if the table gets bumped. Also, in the past I've found really modular systems very slow when it come to building on the go. Great for pre-built set pieces but not so hot if it needs to be put tog
ether on game day itself. Any thoughts?