I took ACEPILOT109's fantastic build and made some slight modifications for Mach 3+ extended cruise capabilities and increased stability. I added a ridiculously overpowered afterburner, after I had already increased the main engine thrust. I then added a small weapons package for basic defense, drogue chutes, refuel probe, air brakes, flaps, a modestly cheated fuel tanks for extended range, and some countermeasures. This started out as a simple exploration of what the X-29 Air frame might possibly be capable of, and it turns out it can handle quite a bit of speed, though it did require some small stabilizing tips.
While it can be a handful sometimes, it's a real blast to fly.
VTOL Flaps down for shorter takeoffs

AG1: Engage/Disengage Afterburner
AG2: Fire All Missiles
AG5: Extend/Retract Refuel Probe
AG7: Deploy/Jettison Emergency Deceleration Drogue Chute