@ BTAxis: is it okay if we 'brainstorm' together without the demand that you implement it for us? If one of us users gets excited enough about some of these ideas, it might motivate us to create the necessary graphics/sounds/scripts...
From the perspective of the player, it is okeh to have the most efficient tools for the job when the mood is serious. There might be times, however, when we might be willing to forgo the standard loadout for something unusual or 'fun'. Swords, anyone
http://ufoai.ninex.info/forum/index.php?topic=2230.15? Therefore, there really is no such thing as too many weapons on the human side. The only issue here is whether a particular weapon is exciting enough to be used sometimes. If there is no interest in using it, THEN there's no point in including it. In either case, i wouldn't expect you to do more than take what we create and patch it in.
So in that spirit, let me offer another trial balloon: a bullet that has been variously called an Accelerator or GyRoc. The idea is that these large caliber bullets have a built in rocket motor. Therefore the primer would be much smaller than normal for minimal recoil. After leaving the barrel, the rocket causes the round to accelerate until impact or burnout. This would allow an Accelerator pistol or SMG to comfortably fire a 15 mm round which could in turn have a payload such as armor piercing or HE. An Accelerator rifle or MG could have a 20 mm round. The limitations would be weight and a somewhat lower accuracy. Plus i haven't yet decided whether this should belong in a new tech tree, or have it branch off something existing [Bolter, again?].