Specific things to add on my contract before enlisting?

You can't add anything to your contract. This is not a civilian negotiation. Your MEPS Counselor can only put what the law and regulations allows and requires. You'll be offered everything there is available to offer that you qualify for.

When you sit with the Guidance Counselors at MEPS, they will tell you everything that is available at the time of enlistment. There are some schools that pop up from time to time like Airborne school. Those have less to do with you and your scores and more to do with current needs of the Army. I'm currently on recruiting and tell people every day..."it's not that you don't qualify for something, it's just that the Army doesn't need that right now". You can be medically cleared for Airborne training while at MEPS, but that does mean that they need Airborne personnel right now.

Don't know if it still applies - when i went in in '84 I had college credits. That got me an automatic E2 upon successful graduation. What I did not know was I could have asked for eligibility for Meritorious E3 with the college credits I had. I could have graduated boot camp an E3 had I known that.