I would love Fenrir as a summoned Egi, but doubt it will happen too. Main reason being, each class/job has the same number of skills. Summoner already overwrites 2 of them to give access to Titan and Garuda, so if they give more summons to Summoners, they would have to give more skills to other classes as well. I'd also love Leviathon as an Egi but that's just me =p