The ballistic shield should use the weapon slot.

[Double-O Deal With It]

I feel like with the ballistic shield your encouraged to use your primary weapon. This really limits what kind of support weapons you can take without it being awkward. If you could take a backpack with the shield it would work well with being a support gunner for the recoilless or autocannon. It would also be interesting to pair it with a shield generator or guard dog.

[Eudicots]

Seems broken and incredibly weak at the same time. If you pair it with a shield generator then you can just speedrun through blitz missions being essentially immortal, but if you playing in a team you'll just be a tank. Too weak to CC or deal with armored enemies.