I like this design quite a bit! However, if its going to be expressly a spacecraft then the intakes on the thrusters are not realistic, yet if it's an in-atmosphere vehicle they look very good. The front half of the vehicle looks very good, but it's hard to tell what exactly is going on with the tail.
Another suggestion is to connect the wings above the fuselage, but that's more of a ascetic choice than any kind of design problem. Overall, this looks great, keep up the good work!