Addtional Character symbols in names

Just curious if we can use underscores( _ ) in names why can't we use other standard character symbols like hyphens ( - ) even spaces :o It would allow for a lot more customizable and proper name creations.

Especially in PoE since your character is not deleted upon death and if you like the hardcore leagues, once your character deaths start piling up, coming up with new names becomes very hard. Especially if you want to keep your character as a template to resort back to now and then for any new characters, so you can't delete it just to get your name back.

Thoughts?