I'll probably be entering again, but be a lot more chill with it this time. I worked myself to the point where I didn't sleep for 3 days at a time and my comic quality suffered. The stable pay opportunities are too good to pass up, and theres no denying the bonus of sharing your comic with more readers.
As for their mature terms, I think its based off how much happens per chapter. None of the webtoons are full on gore all the time, though allow it from time to time. It's the same thing as how many cuss words your allowed to say in different rated movies.