First of all, I’m so sorry for the late response. I’ve taken some time away from the program but I’ve got some good news regarding your question. I personally don’t plan to add that – but you can!
As of the update I just released, you can now create and edit your own sprite styles for TDSM. Adding a weapon layer is somewhat complicated and requires programming, but I’ll be releasing tutorials and documentation in the near future that should make it more accessible.
Thanks for your interest!