Nice looking bird! You should have plenty of thrust to get into orbit. Do a dipper to get enough altitude for an orbital burn. If you don't do this then here's some simple steps/instructions. You need to get to the altitude where your jets are just about to cut out. Then, max out the speed on jets alone. Next, fire up your rocket/s until your acceleration eases off. Fly level, this will start to pull you down. Sink down about 5km so you have enough air to point back up to 45 degrees. As you climb pull back on the throttle as you run out of air. If your apogee is over 40km by the time your thrust is less than full rockets then, you should be good to switch over to rockets only for your climb into orbit. My non air-hogging SSTOs have similar thrust and air intake balancing as your plane and easily get into orbit with about half fuel left for Mun and Minmus transfers. Your other problem would be due to the underside of your craft having more drag than the top. As lift(from your wings) decrease at higher altitudes, drag becomes the dominant issue. Solutions? Moar reaction wheels is always fun, especially for dropships. But, I'd recommend some radial intakes at the top rear to balance the drag(and give you moar air). Win, win.