In the end it is also a gameplay decision. I fucking hate DoD for its run and gun arcade style gameplay. There is a reason why SMGs the PPSH41 of all has a crazy recoil and bad accuracy while at the hip. To discourage spray and pray, run and gun type games. This is meant to be slower, more meticilous type of game and it is thanks to limitations like those.
I love those people who come on a sever with a SMG and run like mad trying to shoot you. I crouch down, take aim and kill them. And they scream hax and bs and all that good stuff.
Please, leave it the way it is. I actually have no problem with smgs at all. It takes practice and getting use too. With the mod, the mp40 and smgs in general were very accurate at the hip, to where I never used iron sights with them. When I started playing ROOST, WOW. I was shocked by the difference in the SMGs. And it took a few days for me to get used too, and I did. I love it now.
So please, relax and think of gameplay as well as realism. I think its very realistic and for the sake of gameplay good decision to make this inaccurate in hip mode. And also, read my previous statement as well.
While in hip mode, the weapon does not point and shoot at the center of the screen as if there was an invisible magical cross hair or point of aim. There is none, as you move, the gun moves so does its point of aim. So any time you take a step the point of aim moves, drasticly. So when you are moving and trying to shoot, your bullets will fly all over the place, because your point of aim is going all over the place. Remember this!!!