So you people just dump everything into your Ortliebs? No bags? Let me understand this correctly: your repair tools are simply freely mingling amongst your food? And how do you separate clean and dirty laundry? You do a sniff test on your underwear every morning to find out which one to wear next?
I do kind of agree with you on this one.
What I do is one bag for clean laundry, one bag for dirty laundry. The dirt laundry bag is placed inside the clean laundry bag. Now I have one bag that holds all my clothes. When I set up my tent, I take this bag out of my pannier and throw it into my tent. The next morning, I put the bag back into the pannier. This is extremely convenient. The pannier never comes inside the tent. The pannier is dirty and I like to keep the inside of my tent clean. I can't imagine groveling around inside the dark pit of an Ortlieb pannier in order to find a pair socks. If I had to do this everyday I'd get fed up very quickly.
I carry clothes as sets in ziplocks or in small individual stuff sacks. With ziplocks, I can see into the bag to see what has been used and what hasn’t. Stuff sacks are a bit more problematic and are either color coded or have numbered tags on them. Stuff sacks are easier to use with bikepacking bags because of the shape of the bag.
There are not that many separate plastic bags. Clothes get a bag. Food and stove gets a bag. Repair tools get a bag. Electronics get a bag. The sleeping bag and tent do not go into bags. These two already have their own purpose made compression sacks. That's pretty much everything that I carry on tour. The other remaining small items such as toiletries, I carry inside a Carradice saddle bag.
Food or food prep gear
never goes in a bag anywhere close to clothing whether I’m using panniers or bikepacking gear. Nor do panniers go in a tent with me
especially food bags. I live in bear country and don’t need midnight visitations.
I never carry anything outside strapped to the rack. I find 4 panniers and a saddlebag more than enough room.
Here’s where we differ. I would never put a tent inside a pannier. First most of the tents I’ve owned wouldn’t fit. They usually have 19” sections to the tent poles and won’t fit in any bag I’ve ever used. But that’s not the main issue I have with carrying tents inside panniers. Tents can be very wet in a morning due to dew or perhaps rain. A wet tent in a water proof bag will quickly lead to a mildewed bag. A wet tent isn’t likely to completely dry if carried on a rack but at least the moisture isn’t trapped inside a water proof sack. My sleeping bag is carried in its own waterproof bag outside the pannier because it doesn’t need to be carried in the bag where it takes up room.
You guys are using the wrong kind of plastic bags. What you want are commercial restaurant bin liners. These trash bags are designed to contain half-finished soda cups that people discard. They are engineered to never leak and are extremely durable. They are also available in transparent. There is no need for any kind of ziplock or other closure system. Just give the garbage bag a few twists, fold the twisted part down on itself, and stuff it in the pannier. This is 100% waterproof even if you thrown your pannier into a pond. Your clothes will be bone dry, guaranteed.
I really doubt you are going to be able to find a commercial bin liner in any size much smaller than 33 gallons (125L) which is, roughly 5 times larger than bag they would have to go into. They are about 125 times larger than what I need for carrying a set of clothes. Seems like overkill.
There is no need to carry a pillow. Take your clothes and stuff them into the above sleeping bag compression sack. Compress the sack to your desired firmness. There's your pillow.
Been there. Done that. Got the crick in the neck to prove it.
This pillow is relatively cheap, very light, and packs down to an extremely small size. It goes in the stuff sack with the sleeping bag along with my sleeping pad. I’m already sleeping on the ground, I don’t need to make the experience less comfortable.