Good points, the thermals on a calm day will be a problem if you don't plan for them. The sunny side will have an up draft and the oppisite ridge will have a down draft as the cold air falls in to replace the rising air. The deer will use these to their advantage as far a which trails they will use.
I used to hunt a valley between two ridges that were about a mile across from top to top. It ran North and south and had a very pronounced up thermal on the warm side in the morning and the opposite in the evening as it cooled and the other ridge had sun on it.