I like the concept quite a lot indeed. I'd suggest toning down the firepower a bit, though, unless some of the turrets were made rear-firing only, as 12 fighter 5s is some REALLY impressive damage output there. Also, as to the model, if you were to integrate the outboard pontoon-style things rather more with the Rhino, it would look much better. As it is, it looks like the Xenos must have duct-taped then on.