One thing I missed in the first game was that there's only 1 kind of underbarrel attachment, the grenade launcher. (I didn't find the tactical attachment very useful, so i don't mention it) The options were using it or not.
An underbarrel shotgun would be a nice addition to this game, it will add more variety to the weapon customization, which means more gameplay options.
Please, share your thoughts about this.

Isn't it going to return?

Now, there are two underbarrel attachements, the Hologramm attachment and the Grenade Launcher. A underbarrel shotgun would be nice, but still, a proper shotgun would be better.

It would seem appropriate for a one weapon type of game. Not Crysis 2.

Nuke underbarrel attachment?

Anti Hologram or Hologram catcher attachment.

Well, I found out in the demo that there's a shotgun attachment... and a gauss attachment, too!