Turtle’s shield is actually really small (I don’t know if this is the final version of the shield). The way it is now your most likely to get shot at if you stand behind it. Crouching by it will actually cover your entire body from damage, but the shield is quite one-sided so enemies could easy kill you if they went around the shield.
I also worry that the shield could block paths. And does/will the shield have “Hp”? By this I mean if it’s destroy able or not. Heavy mercs like Nader, Rhino, or Fragger would be really annoying behind that shield in my opinion.