If you could go back and change one thing in your military career, what would it be?

I would have never married my ex :)

Joined earlier. I joined in '08, if I could go back I would skip college, and join at 17 in '04. Would've done Airborne in my initial contract and gone Active Duty.

I vote for be a better follower, I was always kind of idealistic, thinking I was going to bring real leadership to an organization, make transformational change, etc.
What I have found, you mainly keep a seat warm and update the boss, you manage the continuation of operations...keep the ball rolling.
If that sounds bad...just my experience. When being micromanaged, just say, "yes boss, tell me exactly what you want me to do..."