Ironically, heavies probably have the lowest skill requirement and smallest efficiency gap from militia to prototype. I seriously doubt heavies are deterring new players anymore than them just being stuck in militia gear. One of the most effective newbie strategies is toting militi heavy forges or hmgs along with newbing it up with a heavy suit and a rail rifle.

You may not like heavies but that's just nonsense that heavies deter new players. If anything low meta level heavies generate tons of butthurt from proto assaults and proto scouts. They also generate tons of butthurt from people who don't think before they act... like walking into closed quarters with anything other than a close quarters weapon. If there's a heavy waiting around the corner with a hmg... you kind of deserve to die. That's the guns purpose. On the other hand, you can wreck heavies in long distance skirmishes if you have gun game. They leave cover and you murder them. They don't leave cover... flank them. They aren't going anywhere. Are they clown car-ing in a LAV? Anyone in a LAV is going to wreck you if you have 0 av support, so I consider that a moot point. LAV turrets alone can kill most players if caught in the open and the LAV driver knows what he's doing.

Edit: I say the efficiency gap is small because although proto heavies will have about 500-800 ehp more than a militia variant. The massive hitboxes on heavies make it highly unlikely that you will miss so realistically good players will down a proto heavy maybe 2 seconds after a militia heavy. Heavies are force multipliers like logis but like logis, are pretty easy to down if caught out of their element. The hitbox and slow moving aspect is also why commandos aren't considered godmode assaults. Because, being slow and easy to hit is pretty bad.