Identical tiles within the same rectangle are only drawn in one call (as long as the tilemap is setted for that, which is by default).
So you are saying that if I use only one tile and rotate it, there would be only 1 draw call for it (instead of 4 draw calls for 4 tiles). Also, are draw calls used when the tilemap is invisible ?
I personnaly remember doing once in a bubble bobble type of clone (never really gone too far yet into it) having different tilemaps (one graphical only with collisions off and one that used collisions but set to invisible), that would let you have a collision different than the graphics if you want it that way.
That is what I am doing now since is a RPG map (like Pokemon/Zelda).
Your proposed alternatives will probably not show up any significant performance difference. The way to check it is to see if you can measure any performance difference; if you can't, it doesn't matter.
So the performance increase would be minimal to none ... I've thought that, but wanted to make sure. My maps will be from 2000x2000px to 3500x3500px with tiles of 72x72px.