Undrave
Legend
I think I have been pretty much convinced anyone with a Martial flavor needs an extra-attack. There are enough sneaky system features that play off of it.
There's just not a lot to base off of in 5e so using ways to make use of what's there is the best way to go about it.
In 4e I actually advocated for the Warlord having Heavy Armor be much more accessible than it was. Flavorwise a Tactical Warlord with super high intellect and Hide and Shield was basically just as well Armored as a Heavy Armor but not necessarily better for the flavor ie Knight Commander is basically one of the root things mentioned and one of the Early on Paragon Paths
4e Warlord had Chainmail as proficiency though.