I'll go a little farther out on a limb here. With an all new modular rifle system chambered in an intermediate 6mm round (between .223 and .308). The basic weapon would have an adjustable gas system, with a piston. There would be carbine versions, a bullpup version, a regular infantry rifle version, and a designated marksman version.
There would be a SAW chambered in this caliber as well, based on the SAR Ultimax.
The GPMG and mounted weapons would be regular .308 variations of the FN MAG.
Plus the wonderful M2 big .50.
There would be small numbers of specialized suppresed rifles chambered in a whisper cartridge based on the regular cartridge.
Pistols: Not sure, something simple. in .45.
Subguns: Don't see much need with good quality light carbines in abundance, but the UMP in .45.
PDW: Not sold on that idea quite yet.
There would be a SAW chambered in this caliber as well, based on the SAR Ultimax.
The GPMG and mounted weapons would be regular .308 variations of the FN MAG.
Plus the wonderful M2 big .50.
There would be small numbers of specialized suppresed rifles chambered in a whisper cartridge based on the regular cartridge.
Pistols: Not sure, something simple. in .45.
Subguns: Don't see much need with good quality light carbines in abundance, but the UMP in .45.
PDW: Not sold on that idea quite yet.