Your photos of that girl look phenominal, I'm not even sure why your asking this lol.
These two photos look nice though. Lightroom is great isnt it? It takes all the tools you actually want and puts them in one place. Just dont "push" anything far enough that it appears to be extensivley edited. Super high contrast or high clarity effect always look amateur.
Watermarks are a personal thing. People normally just make those themselves I think. You could scan your signature and photoshop the background out, then apply a glow or something to it. That way you garuntee nobody else would have your font lol. I have yet to even make one. I almost don't even care.