A lot of that is the armour, although she still isn't, er, small. She did end up a bit bustier than originally intended though.
Different weapons is definitely an option. I could probably adapt that weapon into a standard lasgun and something more exotic like a meltagun, without too much trouble. A chainsword or ordinary sword should also be easy enough to do (I've been meaning to do a chainsword anyway).
As for the next sculpt, while looking for inspirational artwork I was extremely inspired by some Ecclesiarchy images I found so I think I'll do some of those next. Definitely a Cardinal, which I've already started on earlier tonight and a Missionary Hero or Drill Abbot. I may do a Soritas inspired bodyguard character as well (I'm not sure I want to do another armoured female so soon).
I'm also still considering the Stormtrooper. I'd want to give that at least two head options (one beret, one kasrkin helmet and possibly a Death Korps of Krieg style helmet too). I'm also considering different arm options as I intend to try and make it a bit more modular than my usual sculpts.