Deleting your character is not something to take lightly. It's not like cleaning out inventory or something, its a character.

I think the limit is fine. And hell I'd be fine if they did away with the one time allowance and left the deletion as permanent. There is absolutely positively no reason for you to delete your character unless you don't want to play that specific character anymore, ever again, and are deleting it to make room for another.

Want to quit the game? Leave your character there, in case you come back.
Having drama going on you want to escape? Server transfer, name change, fantasia, or just blacklist and ignore them. Or make an alt to play on till things die down.

I see absolutely no reason why completely deleting your character would be the right move. Again it's not something to just throw around all loosely, its deleting a character. Be thankful they even let you restore it once.