I adore the assumptions that you're only sending things to "him."
I'm a female Soldier. I've been deployed. There are women IN the combat zone too.
Sorry for that little rant.
Anyway...we'd love all of the things you mentioned. Some of my very favorite packages contained local newspapers, twinkies, small drink pouches that are for flavoring water bottles, a soft throw blanket (we aren't always rucking around...we have beds :-), snacks are great...but please, please send chewy granola bars and good, salted trail mixes.
Coffee is always happily accepted. Ground OR instant...like I said, we do get back to the FOB/COP on occasion to shower and relax. GOOD flavored creamer makes us very happy. I love hazelnut.
Cup o' Noodles soups, microwavable (non-perishable) meals, easy-mac, Dinty-Moore...we get really sick of MRE's, so any of these are VERY welcome.
Anything that will melt simply won't work. It's HOT over there. 120-140' hot at times.
Footcare kits. The kind with moleskin, little foldy scissors, big bandaids, maybe a self-adhereing ACE bandage in there. Foot powder. Deodorant. GOOD shave cream in a tube (can't ship the cans). Good sunscreen (unscented, SPF 50ish).
I'm sure I'll think of more later...
ETA: You didn't say "he." I was referencing a few answers down below...
OMG...and I nearly forgot. GIRL SCOUT COOKIES! We LOVE them!