Store separate settings for each type of contact form

Right now the settings are stored globally for all contact forms (site-wide contact form and user contact forms). It would be nice to be able to store settings based on the type of the contact form. This would mean that for example a user can attach only 2 attachments on user contact forms, but would be allowed to attach 3 attachments on the site-wide contact form. The same goes for file extension and size restrictions; they could vary according to the type of contact form.