How was your diet when you were active duty? I know that the healthiest I ever ate was in basic and AIT. Your current diet doesn't sound bad, but you could use more variety if that's what you eat every day.
I feel like you're over-complicating the issue with using the heart rate monitor. I made pretty good gains in my run time while in basic and I don't remember any of the drill sergeants having us check our heart rates.
