Guild guide Ohmonir at the Mages Guild in Vivec seems to be for Mage Guild members only - is that intentional?
He is part of the travel network going from Vaardenfell to the mainland. All of the other guides I have seen that go to the mainland do not require guild membership. I realized this when I used the guide in Old Ebonheart to travel to Vivec and then was unable to return via Ohmonir, because I was not a Mage Guild member. So, other than becoming a member, my only option to return to OE was to travel to Ebonheart and get a boat, which was a bit of a hassle.