I'm unsure if its common for legions to have more than one Praetor, or if there were just a lot of deaths among some of the other legion Praetors, but like jeeze the EC had a whole bunch of different praetors.
https://warhammer40k.fandom.com/wiki/Praetor_(Space_Marine)The correct terminology for the Legions true 2nd in command should be "Praetorate of the Ancients of the Legion" so perhaps the "Seniormost Praetor" or even a first among equals type deal.
Calling them Legionmaster is more succinct though. I like Legio Dominus cause its more Mechanicus oriented.
