Why can't I use the C96 as a scout?

Or the Webley as a support? Or the [any class specific pistol] as [class who doesn't get it]? Pistols aren't overpowered and many pistols available to different classes perform nearly identically anyway. Why are we being restricted? The quantity of content for the game already doesn't shake a stick at Battlefield 4.

On a similar note, why are certain weapons so restricted in the variants they get? God know's it's not for realism's sake. Why cant I use slugs in the Trench or Auto? Why is there no Infantry Springfield? It's in the game in Standard Issue. Why no sniper enfield?

The variant system altogether is incredibly restrictive just so DiCE can make it look like there's more diversity and content. Why can't I use the bipod on the MG15 or Benet Mercie without the hideous scope?

You can make the argument that some of this is for balance sake, but restricting customization options for the sole purpose of balance is a really shitty thing to do.