I’m working on something like this for the summer, two different trips, one in the Southeast US which his more sutropical and the trail is rough, so I expect a lot of hiking, but the access to supplies is better. The other trip is in the Rockies, less hiking and better trails, but no access to supplies.
I have done a lot of unsupported distance hiking and biking, what you “need” to have is a lot less than you thnk you need, so forst off:
Skip the tent, instead bring a tarp or one of those “no bottom” tents, use the uni as your center support.
Sleeping bag, go two sided, water resistant, light as possible and compressible.
Pad, cut a full length foam pad in half to cover shoulders and hips. Clothing should be one set, use it daily, dry it at night, an extra set of socks, wash one pair, switch out daily
Cooking, DON’T COOK, skip the stove and eat cold, you can presoak most foods if you want them soft, bring spices for flavor. Rememer that dry foods are lighter, but you need water to hydrate them and you.
Water is the heaviest thing you’ll carry, but if you have good sources you can carry less and refill more. A water bag is convenient, but be prepared for a leak. Bottles are bulkier, but you can fill them easier and they are much better if you need to treat water as one can be “treating” while the other is drinkable.
Repairs, carry a spare tube, get a heavy duty sewing kit and some thin nylon/plastic sheeting (flexible cutting board) for tire repairs, bring replacement bolts for all parts, bring an extra seat post collar.
Basic first aid shoudl include “comfort products” like hand cleaner, lip balm, sunscreen, anti acid (Tums), NSAIDs, pepto, eye drops, small mirror (to help get bugs outta your eyes), tweezers, knife/scissors, tape, pads, etc…
You really can’t carry much on the uni itself, so you’ll have everything on your back, a good backpack is key. Probably need something more than a big Camelbak, take a look at the Osprey Atmos/Aether, I have a couple different sizes, they are awesome for carrying loads while being active, I have used them for fastpacking and backcountry skiing.
Shoot for 20# including pack and two liters of water.
I have mostly done solo and pairs trips, three is a crowd, four is doable. Honestly, I don’t think group cooking is any fun, it takes more time, it adds drama, and in the end you either have too much or not enough food. My preference is for each person to do their own thing for food, you will end up sharing, but that way everyone is independent and can eat when they want, what they want.
One of my favorite trail foods is a chocolate or berry powerbar dipped in peanut butter