Mail auhto is a safety measure. Would be good if they added the option to use an authenticator app tho, much safer. They have it on Blade and Soul as far as i know.
Skill learning is problematic since you need rune stones, gr. rune stone, forgotten books etc. to learn some of them, and at lv.108+ you can't learn all skills at once when you lvl up, since the SP cap is 50b, you need to choose which to learn first.