Long time lurker, I felt that I needed to finally register to reply to this post. I'm a stay at home dad for a 3 year old, a 1 (almost 2) year old and another on the way. Baby care is where I'm at every day.
Diapers: Either you or your wife should keep track of how many diapers you use each day for 2 weeks or so. Figure out how long you'll likely be bugging out for and figure out your carry. You'll either be suprised at how many or how few diapers you'll need. Even when change diapers all day every day you seldom have a realistic number in your head. Keep the diapers dry. I mean really dry. Went swimming this past weekend at the river and forgot a swim diaper for my 1 year old. A diaper that starts out at an ounce or so will literally weigh several pounds when completely full. Diapers absorb ALL available moisture. The factory packaging is only good until you pull the first diaper out, then it's compromised. You need another layer of protection, I don't care how waterproof you pack is.
Even though is might sound like a silly BO piece of equipment for you, an umbrella might save the day. It protects the baby from sun and rain without covering it with a coat. It gives you sun and rain shelter when you have to sit and change/feed. Make sure you sleeping arrangements will accomodate baby. If you don't sleep with your baby now, learning how to do it while zipped in a mummy bag will not be pleasant. I napped with both my kids, both of us could fall asleep snuggled together (safely) when camping no problem.
If you're potentially switching from breast milk to formula in a BO situation, you will get puked on as the baby adjusts. Formula puke is really really nasty stuff to be wearing on your person for any length of time. (I wore it all down my front for a 4 hour plane ride once) Think about that with your clothing choices as well as the baby's. It's quite likely that you'll provide much less comfort after day 2 of smelling like rotting milk, even babies have noses.
Babies don't regulate temperature well at all. This may affect your daytime bugging plans if it's warm. You must keep baby safe first, if this means sitting still during the heat of the day then that's how it has to be. You may be resting during the day and walking at night.
How are you going to heat the formula? If your baby won't drink room temp formula it may be useless.
Just a few things to think about, I'm sure I'll think of more.