Is there any reason I would need to retake the FAA checkride, or the written?

Professional pilots are checked in simulators every six months, so for that reason alone you should want an instructor to re-check your flying, just to be sure that no bad habits have crept in. I strongly advise you to be checked every six months, even if you are certain you don't need to be. It is this system of constant checking and re-checking that has made airline flying the safest method of transport. Even if you are only a private and amateur pilot, you should still cultivate a professional attitude.