The elevation profile is great, for sure, but I meant more like...difficulty, rather than grade? I don't know the exact word to use, but sometimes you have well used, well marked trails and other times you have a "trail" that maybe gets used a few times a year and is more like a choose your own adventure with a rock cairn or two every couple hundred meters if you are lucky.
sac seems a little too broad to me; most trails would be level 2 or below, without communicating much more than a simple elevation profile already gives you.
