• Because the model will always try to use full height, a "face fix" is required.

• The size of the weapon directly depends on the position of the frame, trying to fill the space horizontally. On a portrait it will be the size of a heavy minigun, and on a panoramic it will be a fantastically huge gun.

• The style of the character's outfit depends on how futuristic or fantasy the weapon is.
  

Different styles can be combined with each other in intricate ways.
Plasma gun - Glowing blue elements, sometimes makes the barrel vertical.
Rail gun - Two rail guides.
Lighting gun - Plasma and rail mix.
Rotary gun - There was supposed to be a minigun, but all that came out was a multi-barreled end of the barrel. Or just a few barrels.
Flame gun - 50/50 it comes out either a flamethrower or just flaming elements.
Cannon gun - One large and thick barrel.

Mecha musume - Always gives off a sci-fi vibe, but if you add a fantasy gun, it leaves a bizarre medieval outfit.