Hi,
Im very new to studio photography , so perhaps somebody with more experience will post. Looking at that , if you could lose the snoot cover and diffuse that light source slightly ( something opaque like a lampshade or frosted bowl ) that might scatter the light a bit better i reckon your in business. or why not push the backdrop to the left and vary bouncing the strobe the white roof to scatter it with some " spill " on the subjects head and some on the backdrop.
That or put the softbox half way between the snoot position and the post and a touch higher and lose the snoot ?
Either way , the biggest thing I see is to stop the " burn " on top of the girls head, i have a snoot and played with it a little and never really like what it did. Focussed burn was the best i got out of it..
The other thing is to iron that big crease out of the background. I have seen some suggest spraying them with a mist of water so the crease naturally falls out.
Also it looks like you have another few feet for the tripod to move back ? Id mess about with that and maybe shoot at 70-80 mm , with the lens closed down a bit so you keep the back drop OOF.
All ideas and like i say , im new to studio stuff and just learning myself. As for what your partner gave you to " play with " ,, man your luckuy , Im waiting for a room in my office to become free to set my stuff up .. right now i have to pack away the sitting room before i start to " unpack " my studio 