Starting position for new seat
I'm aware of the effect of slight changes in seat angle, but in mounting a new seat I'm not sure how to choose a good starting position so that I can just vary from there a degree or two at a time. I find that it takes more than just a quick run up and down the street to really tell how a saddle is going to feel, so don't want to have to make too many changes or have to try big changes.
Anyway, many places that I've looked -- such as on Youtube -- say that the optimal starting position is to have it level, which at least gives you a repeatable position if you set it using a carpenter's level. This is easy to do with a typical flat-topped seat, but many seats out there are contoured with a kick-up at the back and/or sloped down at the front, etc. So how do your figure out what "level" means on a seat like this? Putting a level on the seat so it rests on the two high points would be easy, but could easily start you off with the nose too high and make it tough to find the sweet spot.
Is there any way to figure out what the intended "level" position of a seat is designed to be? I always thought it would be nice if the seat rails were made to be parallel to the neutral position of the saddle, but I can see that this is not usually the case.