This is great question and lots of great responses. Like most, I've had dozens of bags. Cinebags, Thinktank, Tenba, and PD and Lowepro.
After something like a million miles, carrying any bag around international airports with medium format cameras and lenses just plain sucks. So here's what works for me. I fly almost exclusively on Delta, except intra-asia and have never had a problem. Delta allows 1 carry-on and 1 "personal bag" for me, that's a camera bag.
I have a spinner Briggs and Reilly as my change of clothing/coat/laptop bag. It also carries a lot of my batteries/charger and hard bulky stuff. On top of that is my Peak Design 30L. I bought it from REI because you support a good organization and get rewards in the form of dividends back.
In it is some Samsung t5 SSD's (and now sandisk ssd) in a tiny pelican, 4 lenses with the largest being the 240mm, and the Phase XF/back, etc. Sometimes on the bottom of the bag I put a Mavic Pro. I also have a small bag of cleaning clothes, color chart, a headlamp, and few other tools and things. I also have an Osprey waterproof raincover. Maybe they PD came with a raincover, but I can't find it, and this thing works and is good for setting it down anywhere and having a place to work from.
Now there's three nice features about this PD that I want to say. One, their inner-bag dividers stick. They don't go anywhere. Not that they could because it's so packed, but if it wasn't, it wouldn't. Secondly the top handle. You know how some backpacks you really have to stretch to go over the rolling bag, not this one. It's really good. Secure but not too snug. Lastly the dividers aren't super padded, which take up all the room in a bag. That's really annoying when traveling, and why Cinebags are terrible (they protect stuff, but lose all their room).
And the spinner bag on the bottom has changed my life. I can travel with a coffee or my phone happily for miles through airports. No more broken wrist. I can run terminal to terminal. The briggs also expands or can be crunched down using these things on the side, so I take my laptop out and put in overhead even on small domestic commuter flights.
The PD 30L fits in every single overhead (a little issue if you try to stuff laptop also in there) but with medium format, I think it's the best I've found.
The other bag that I recently found that may be of use to someone here is the Mindshift Photocross 13. While i'm not a fan of across the chest situations, it's fairly comfortable when used with waistbelt, I can put the XF with a lens and another lens (including the 240mm) in it. WITH my 13" macbook pro. It's heavy, but super compact where the PD isn't. And it pretty much goes flat and has waterproof zippers and a little sidepocket for a reusable water bottle.
So now, I pack the Mindshift in my main luggage from REI (a "hardcase" spinner...see the trend...airport checkin with two spinners is the best) and if I just want one lens or just the drone, I can tackle anything and not be lugging around a 30L backpack with one piece of gear.
I do miss Lowepro and their bag in a bag thing - the roller bag turned backpack. That's awesome. Bulky, and heavy, but awesome. I think Tenba had one (I also bought).