What gear do you NEED?
Lessee.. . You have a gun, calls, some camo.
You'll need a hat, a facemask and some gloves.
I'd throw in something to sit on. I use one or two small foam pads. Some guys like the pad that hangs off their vest. I also pre-position camo boat cushions in my favorite spots.
The rest is all going to be dictated by where you hunt. As a for-instance hunt within a half mile of my own camp. I may put a thermos of coffee in my deke bag, a sandwich and a coke if I'm going to be out long, and then leave it in my first set-up. However, I'm not packing for a 10 mile hike on public land.
Do take these things, even if you're just going out in the back yard:
1) compass -- two cheap pin-ons are fine.
2) matches and tinder (dryer lint works fine)
4) Writing material
Read this: Shamanic Guide to Survival (short form)
The rest is covered in this:
What's in your Bag?
.. . and this:[url=http://genesis9.angzva.com/?p=250]
What's in your Vest?[/url]
. . . and yes, this gets talked about a lot, here and elsewhere.