I've done the nomad thing from months to years. Not always intentionally! Had moved cross country anticipating a company move weeks later, then the pandemic happened and it became years. Trying to do it inexpensively will be painful, compromising on ability or quality will lead to frustraiting failures and limitations.
My loadout was very similar, though I had more clothes and music gear because I was strictly living inside. "Golfing" backpacks that are insulated are very underrated, think the capacity was closer to 15.5L. They don't really make them to accomodate 17" laptops anymore, and you shouldn't have one that big, but the extra space in the sleeve is great. Strong endorsement for American Giant! Especially the heavy zip up hoodies, running pants, and shirts, some of which I've had for almost 20 years at this point, and Oddball socks (if you have big feet).
They aren't for everyone, but the rather thin/rough gym-style towels are great as you can get 3 into the space of a normal one once you've mastered rolling your shit up and they dry quick. When your boxer briefs inevitably wear out, cutting the band off and using them to constrain other things while the leftover cloth makes for great snot/cleaning rags. Save your plastic grocery bags, they're useful for so much and compact well.
Cannot understate how much better this makes air travel. Can still be shoved under the seat in front of you. No checked bags or secondary carryons removes so much potential for bullshit. As the bag is still soft, you have to be deliberate with where you pack things or you will crush them. You'll want to consider the placement of electronics TSA is going to make you pull out, and expect secondary screening. The density of shit in the bag tends to cause this if they're still using old xray machines instead of that new 360 degree shit.
I ended up also lugging around a workstation and monitor. It was worth the logistical pain and my new limit became "fits into the trunk of a rental sports coupe", avoiding planes was worth while everything was still ongoing. I would not attempt doing this with modern Apple Silicon. Can't stand what mac os has become and there are too many caveats. Any high end ryzen laptop with an nvidia gpu is preferable. If you do anything in/with multimedia or streaming, you'll be thankful the first time you can lean on it as an encoder (and the USB 3.2 port will actually be able to handle the throughput of a Magewell USB capture card).
Hard to undersell the 'freeing' aspect. If wherever you are sucks, for whatever reason, it doesn't take much time to be packed and gone. It's not for everyone. Have met some fantastic lifelong friends from couch surfing and renting rooms listed on craigslist, which is vastly superior to AirBNB, where I encountered scams so frequently that I swore them off entirely.
It changes you, too. Once you settle again you'll realize what you really care about.