[otrs] customer.pl or e-mail ticket creation

Hi, Any opinions about the method of ticket creation? We would like to allow the customer to set the priority or SLA when creating a ticket. It would be easy to do using the customer portal, but less convenient than allowing e-mail ticket creation (especially for screen shots). Using e-mails implies developping an Outlook template, deploy it, and make sure OTRS can get the priority or SLA from the e-mail content. Thanks, Ugo