Macabre - can you explain what you a trying to show by your markings? There are any number of ways to mark up a horse, depending on what, exactly you are trying to show.
Generally though, you will want to set dots on the center of joints... Then draw lines to intersect those dots. I find you will get more accuracy that way.
Most of the time you want to make sure , for general conformation, you have a body length line... As just about everything is going to be compared to that length in some way. You will want to mark your horse's LS placement as it is an important marker, and important joint.
The information is good... However it misses on one level... The fact that conformation is the sum of a whole.
Being able to see faults is a great first step... But knowing how those faults, or traits will work with or against other aspects of the horse's conformation is actually the only way you can tell if any given fault is forgivable or a big time issue... And anything in between.
Knowing these things is important when you are training, and especially breeding, for any specific sport, it may mean you will have to focus on certain training points or that you even have a horse completely unsuitable that will go unsound should you try.
On the whole, not a bad visual aid... But I would like to see more comparative terms in order to make it truly useful... Without them it is incomplete... I will say it again, conformation is the sum of all parts... Not just individual areas.