I do see the training value NTC and other training centers have but is there any other reason to go there unless your deploying?

I saw NTC as less training at the individual level and more of grading the unit as a whole. 

The NTC, JRTC and the CMTC in Germany all serve to validate units at the BDE/Regt level. Now you as a young Mortarman may only see the platoon and maybe the company AARs at your level, but the BNs and BDEs are being observed and evaluated as well. This gives the DIV, BDE and BN commands the opportunity to see where they stand as far as the training that they have undergone from the PLT STX and CO FTX and BN maneuvers training back at home station. It shows the Big Army "where" it's units are in relation to their war time missions and areas that they need to improve upon in order to be able to meet these missions. Back in the day, we used to undergo ARTEPs, CALFEXs and multiple training exercises to ensure that we were able to stop and defeat the Warsaw Pact forces we were trained to meet. The Army is going to be resetting to a non-war footing and these rotations will be back to where they were prior to OIF/OEF and will be tweeked to meet the most current threat as assessed by DoD and the powers that be. The training is vital and is more than just a ramp up prior to deployment. 

The Army is going back to its original mission of being prepared for war - rather than actually having a war to go to.  Being prepared is probably the more difficult mission because of the lack of certainty and timeline for which to be prepared.  We have no set timeline for when we need to be ready.  We need to be ready NOW and we need to STAY ready.  NTC is just a gate that units go through to tell the Army, "Hey, we are ready to go when you tell us to go."