I’d like to add an alias to author Γιάνης Βηλαράς. His first name, Γιάνης, is normally spelled with two nus instead of one but he used his own spelling system in his work so that’s what I used on MB. I’d like to add the common spelling as an alias so that people who aren’t aware of the spelling peculiarity may be able to search for him successfully but there’s no way to do that currently. Should I still do it?
EDIT: Same applies to his work, Η ΡΟΜΕΗΚΗ ΓΛΟΣΑ. The common spelling would be Η ΡΩΜΑΙΙΚΗ ΓΛΩΣΣΑ or Η ΡΟΜΑΙΪΚΗ ΓΛΩΣΣΑ (ideally I’d like to add both).
Yes, just add any variant as alias. We don’t have any specific rules. It’s better to have all different variants as alias. As you said. It helps to find the correct authors or works.
I would just add that MB has a hint alias type that is used to mark an alias as wrong and is often used for typos. We don’t have BB, so we should avoid adding actual mistakes to the aliases. But what you describe is more of alternative spelling,so it’s appropriate to add.
As for which should be the main name, you should use the one that is currently seen as official, not a historical spelling. If his chosen spelling is generally still respected (e.g. in encyclopedia articles, etc.) then I would be appropriate to use it. If not, it’s more of a historical spelling, and should only be an alias.