In the meantime, a little update on my rifles:

The weapon on the bottom left is the original 'energy rifle'. The two rifles on the right are my first 'automatic rifles', they're basically the same weapon except for the chain bayonet. The ammo drum needs to be altered though. It's the one from the
'eight-shooter' pistol, but I need to tweak it a bit to represent a smaller caliber.
The rifle on the top left is a new energy weapon, I kinda imagine it as a 'light' beam cannon, basically a 40k lascannon in rifle form (a Hellgun I guess?). It has a lot of components in common with the other energy weapon. I like the idea that a lot of the tech here is rather modular and compatible, meaning that both energy weapons can exchange ones' batteries and other components if needed.
Regarding the sprue, my original idea was to have a pistols sprue with about 10 different pistols on it, and a rifle sprue with the same number. As for the sprue itself, I really love what Pig Iron Productions did with their
Near Future Irregulars, so that the sprue itself can also be used in a more direct way. Maybe in this case the sprue would be more high tech shaped rubble rather than bricks.