As a Sorcerer myself, I greatly disagree on a lot of your opinions. You didn’t do enough analysis on how the skills work and how to use them.
For example, Riding costs minimal SP if you just jump on -> use the skill -> jump off. There’s really no reason not to do that and their attacks are very strong.
Besides that and some other things, yes, Sorcerer is in a bad spot. Supposedly Necromancer is quite strong, but I haven’t played it myself. I hope they do some changes to Sorcerer, even if it’s just quality of life.