So, people want to do something crazy next round for design, just to fuck with RNGesus?
Hmm...
Genetisaur: Using advanced genetic engineering, which we totally have and is not just propaganda, we modify a native species of Moerth into a 4m tall ravenous beast. A chip implanted in its brain (which we also totally have the tech for) allows basic commands to be given by its 'handler'. Thanks to its superior biology, it can shrug off small arms fire, and can even survive losing several limbs, thanks to its redundant organs, rapidly congealing blood, and fast-growing scar tissue. Not even destroying the head will put it fully to bed, since a large part of its motor functions are governed by a sort of secondary brain in the torso, a large cluster of nerves (with mind-control chip) that will cause soldiers to run in terror as the headless beast bears down upon them.
Again, we totally have the technology to do this.
More sensibly,
Scaythia Rifle: Bearing only a passing resemblance to the Printed Pistol, this rifle, while containing several printed parts, also contains parts that have been created using more traditional methods, out of quality materials. Like the PP, it is a fairly simple device, of a tech level that would not look out of place in the earlier parts of the 20th century. Do not discount it for this reason, though- the Scaythia makes up for its simplicity by being especially reliable, easy to fix when it does break, and possessed of decent range and accuracy (or an amazing range and accuracy if compared to the PP). It uses a clipazine, and is 'automatic' in the sense that bullets are automatically chambered, allowing the user to focus on firing.
These weapons, whilst possibly more expensive than the PP, should still be simple enough to manufacture that they can be distributed to the majority of our forces.
I'm assuming we don't have the blueprints for actual modern rifles, or we would be building them already, so it makes sense to start simple.