1. Would it be possible to add an undo button for when changing a route goes wrong?
2. I think this would also work really well for planning routes and/or measuring their precise length. In fact, I have been looking for such a tool for ages! One like yours which also allows taking small tracks and paths and not just roads! Unfortunately, currently it's still somewhat difficult to select the precise route as changing it in some place might suddenly change it almost entirely. (Again, an undo button would be nice.) I assume this happens because Trail Router still tries to minimize a certain loss function? Would it be possible to disable that entirely, so that one could "free-draw" routes?
[UPDATE]: Just noticed that one can actually disable all routing preferences. This seems to be doing the trick – very nice!