I think 48 was difficulty walled before update, but I beat it just as update released, and after stopped at ~52 (in one strike) I was inspect for new features and now I still at 52 working with crew etc...
Well I hope you get through your current wall soon and punch through to the next base to get resources growing on that. My setup for a long time has been 4 beams with 2 laser cannons in support mode, but I may have to rethink that setup.
