Having the 9 slice margins in the index is the part most kits leave out. One question: the overlays cover the pointy top hex grid, but the path arrow set lists iso and square only. Is a hex arrow set planned? On hex the corner pieces need 60 and 120 degree turns instead of 90, so the square pieces cannot be reused there.
Viewing post in Brass Tacks - Tactics Grid & Battle UI (Pixel Art) comments
Thanks! Glad the 9-slice margins stood out. You're right that hex needs its own 60° and 120° corners, so I've added them: v1.1 is up now with a hex path arrow set for the pointy-top grid (start, end, straight, 60° and 120° corners in all 3 colours, 81 tiles). The README covers the hex autotile rule and neighbour offsets, and the last screenshot shows them on a hex board.