We do week long bivy trips in Idaho, and I take instant coffee from Trader Joes (has cream and sugar in it, which i like!). I think they are cheaper than Starbucks too. And I like them more.
If you are a true coffee snob, JetBoil has a lightweight attachment to convert the pot into a french press. So if you hate instant coffee, it's a lightweight alternative. Its less than an ounce, I think.
Regarding the Jetboil being heavy, it really isn't. I have the titanium, and when you factor in the extra efficiency of the Jetboil (ie, less fuel to carry), the Jetboil is about as good an option as anything. However, with all canister stoves, they can be a problem if you are in really really cold weather--but probably not the kind of cold you'll experience on a bivy hunt. And, if it did drop low unexpectedly, you can warm the canister in your bag.
Mountain house meals are hard to beat, but you can make your own too. I like to dehydrate venison and add instant potatoes, gravy powder, boulon, salt, pepper, and top with french fried onions (like you would put on top of green bean casserole). Keep the onions seperate while the rest rehydrates---delicious! Plus, those onions are like 200 cal/ounce!
I go heavy on nuts, especially macadamia nuts, because they are the heaviest per ounce. Sunflower seeds too (shelled).