Given how lasers and EM accelerators generally take large power sources to truly shine, and that their main advantage (huge exit velocities) doesn't really come into play in infantry combat a combination of conventional guns and blast launchers seems optimal for this task. With this in mind I present a collection of small arms built around the same core of 7mm rapid fire combustion gun, complete with 100 round magazine and compact radioisotope energy source, complemented with additional metalstorm-style launcher modules firing a variety of specialized munitions and suitable ergonomic frame with lateral radiating surfaces integrated into stock and accessory rail.
The PDW is the most lightweight and compact option complementing its primary mechanism with 16 shot underslung metalstorm system firing firing miniature 10g fragmentation rounds suitable against soft targets. It's intended to allow use both on the surface and in cramped corridors, where fast burst of frag will provide devastating destructive potential and reduced risk of unintended penetrations at the same time and compact frame will aid manoeuvrability and, conversely, the lack of increased penetration option won't be as much of an issue.
The AR is the intermediate option, doubling the mini-frag capacity and complementing it with twin 12 shot 100g jacketed osmium penetrator packs for situations demanding increased penetration.
Finally, the battle rifle sacrifices compact size and half of it's smaller sibling frag and AP capacity to accommodate single shot overslung launcher capable of firing around 1kg dual purpose EFP/Frag warhead capable of defeating even warship grade armour (with standard naval fabrication techniques the launcher will require post-manufacturing modification to allow recoilless launch or detachment and free recoil of launch container at the moment of firing). Alternatively the launcher can be replaced with similar launch system firing a projectile or projectiles in the same approximate mass range.
To simplify the necessary targetting systems and aid use after long period without training the launcher modules all have similar exit velocities to the main gun.
To provide environmental sealing and modest amount of protection (hand weapons aren't going to survive direct fire anyway) without compromising their light weight, the weapons will come encased in a layer of UHMWPE weave.
The core weapon module:
The power source:
No mods.
I admit, I mostly wanted to see if I could make anything resembling actual weapons given ship editor's constraints. In this regard I declare these creations of mine a success.