How hard is for a reservist to go to active duty, with the current state of the Army?

I think a lot of it has to do with your MOS. Critical shortage MOS's would probably be easy as hell. "Needs of The Army"..

As a current Recruiter(meaning Tuesday when I return to work, my place of duty is a recruiting center and I put people in the Army everyday), I can tell you that because you're a SSG it will be tough. We go by a set of prerequisites called the Business Rules. They can change every other week so Google can't help you. With that said, you can almost always go AGR as a Recruiter, the Army needs them. If your open to Special Forces, that is also a possibility if you are open to losing a rank. There is also the issue with your current unit. As a SSG, they may not want to lose you and can deny your release. Your MOS is a factor also, certain MOSs are the "flavor of the month" and can be filled easily. Your best bet is to go see a Recruiter in your area so they can sit down and go through the manning and business rules with you. Good luck to you SSG.

A way around it would be to find deployments, there are always deployment list, your unit should have a them and you should be able to look it up on line.