I never really liked the Eleventh because of that - it was solely combat, why the hell would they hate hado?
Also, this is the Joint Combat Division. Assuming that Vanguard was Pure combat, that would be the old Eleventh - Reservoir is the mixed one.
Captain of eleventh never had to be a Kenpachi. Eleventh is just the strongest is the Captain; Kenpachi picked up his name because he murdered like everyone in District 80.
Also: Please, please, please remember that Captains will only very rarely enter combat - if you're scrapping a captain for a captain of an opposing division, one completely at odds with your original, keep in mind that a Healer/Science is even less likely to fight than the Joint Combat ones.
S'why I'm about to start designing an unseated to mess with.