Bryan,
While the idea itself is sound, IMO, using a subgroup for this would really depend on how many mods you have and whether you want to have any conversations, attachments, files, photos, etc, archived for later reference or reuse when a new mod comes in, etc; if yes, a (private) subgroup would work great with all the features GIO has, although keep in mind that if you don't already have a subgroup already, there are some addressing changes that take place as stated.
Taking into account the caveats already been stated, if you don't care about archiving anything or have maybe a few mods, it'll be less work just doing it through an email list; or use the +owner address as suggested, but keep in mind in this case, in order for this to work effectively, all mods will have to have the receive owner email to ON otherwise this scheme will not work well.
Cheers,
Christos
Christos Psarras