First: amazing project. I'm really impressed. Once you build a solid base people will bombard you with suggestion of new weapons and killing methods.

Somebody mentioned konashion: While his blog is dead for at least 4 years a lot of forums full of mods and custom skins exist. Once I found a 8 GB torrent of ALL anime characters you could think of.

And I believe the success of SDT is simple core concept and extremely easy modding. Hell once I made princess from Angel Corps skin.

So Dorumeka. Keep it up and if possible let it be as moddable as possible.