I have much the same wishlist as you, and also haven't found anything that ticks all of the boxes. My day job is network/sysadmin/IT, which mostly involves remote connectivity to other hosts, so my local CPU grunt needs are not particularly heavy.
That said, given the dearth of good options out there right now, I just replaced an old MacBook Air with a Surface Book 2, and with a few exceptions, I couldn't be happier right now:
1. This touchpad is just as good as pre-Force Touch ones from Apple. No joke. (If you must have the super-size ones with the Force Touch feedback instead of the "spring-board" style real button click, sorry...nobody else has that. But the non-Force Touch ones were "best in class" before, and that wasn't very long ago...)
2. The keyboard is easily the best laptop keyboard I have ever used. And that's coming from someone who used ThinkPads (I had the 770, the T42p, and the T60p) before switching to MacBooks, and who uses a Model M daily while at my desk. :-P
3. I have the base-model Surface Book. It's only a dual-core i5. But, again, I'm fine with that. The CPU is also housed in the screen, since the screen is made to be detachable from the keyboard. And since I have the base-model, I don't have the dGPU in my keyboard base either. So the base of the laptop stays cool while I use it on my lap. Oh...did I mention that the entire device (both keyboard base and screen) on the non-dGPU model is fanless? So no moving parts in the entire thing, noise-free, and isn't constantly sucking dust from the surrounding environment into itself.
4. There is a battery in both the screen and the keyboard base. Combined, I get amazing battery life, easily 8 hours or more depending. (I use it in laptop-mode 90% of the time.)
5. Screen on this is fantastic. Higher DPI than my 15" Retina MacBook Pro from 2012, way brighter, and the backlighting is more even. (I have the Samsung LCD on my 2012 rMBP...the model that never developed "image retention". I think the SB2 panel is made by Panasonic.)
6. It's got 2 USB-A, 1 USB-C (sadly no Thunderbolt, but it can handle DisplayPort), and a full-size SD.
7. Repairability is one area where it really falls flat, and in even bigger ways than the past MacBooks I own. :-( This thing I think got a repairability index of 1 (out of 10) from iFixIt. It's a sealed box for all intents and purposes. What really pisses me off, though, is that the SSD is not soldered onto the mainboard (it's a standard M.2 module), but there is absolutely no way of accessing it without basically destroying the computer in the process. If there was ONE area where I wish Microsoft had NOT taken any cues from Apple...gah, don't get me started. (And even then, at least with pre-2016 MacBook Pros, you could take the bottom cover off and get at the storage module in an emergency.)
8. The particular model I purchased ranges from $1,100 - 1,500 USD depending (list price is 1,500 but it's usually on sale). Don't know how that translates to your specific market.
9. I have not tried to use "desktop" Linux on it. I have booted SystemRescueCD off of a USB flash drive, though, in order to make a bit-for-bit image of my current Windows installation, and that worked fine (though to be fair I never bothered to start up X11). My understanding is that a lot of the hardware is supported even on current models; you can check out https://www.reddit.com/r/SurfaceLinux/comments/7kazwp/curren... for more details.
I jumped on the Apple bandwagon circa 2007ish, when I bought a Mini. Prior to OS X (and its nix underpinnings) + x86, I paid them no mind, but both of those things put together plus their reputation for solid hardware engineering finally won me over. Shortly after that, I got myself an Air. Before that I bought and used ThinkPads exclusively. I also have the original 15" Retina MBP from 2012, which still runs great.
But I have slowly found myself leaving the Apple ranks over the years, and the 2012 Retina was the last Mac I spent money on. I also ditched iOS (and iPhone along with it) for Android (long story) well before macOS began to take a back seat for me.
In January, I requisitioned a Surface Book 2 from my employer, and it has been fantastic so far. Easily the best laptop keyboard I have ever* used.
If you told 20-years-ago me that I would be buying PCs manufactured by Microsoft and praising them, I would have had you committed. But it has been fascinating watching a hungry Microsoft compete in this space...
At least with the MacBooks, you do have the option to downgrade back to a previous version of the OS, if you find the performance of the new one not up to par. So why not go back to the version of the OS on your Air that you were once happy with?
For the record, I have the same rMBP 2012 model that the person you're replying to talked about, and it still runs great. But I'm typing this reply to you on a MacBook Air from 2010, running macOS 10.12 Sierra, in Chrome. Still works surprisingly well...
For most consumer PCs, I have no problem with most things being soldered on like RAM, CPU, etc...but soldering on the storage is unforgiveable. And it has nothing to do with being able to upgrade it, but rather it's about the problems this introduces (and the options it limits) when it comes to data recovery when your machine inevitably @#$@#s up.
That said, given the dearth of good options out there right now, I just replaced an old MacBook Air with a Surface Book 2, and with a few exceptions, I couldn't be happier right now:
1. This touchpad is just as good as pre-Force Touch ones from Apple. No joke. (If you must have the super-size ones with the Force Touch feedback instead of the "spring-board" style real button click, sorry...nobody else has that. But the non-Force Touch ones were "best in class" before, and that wasn't very long ago...)
2. The keyboard is easily the best laptop keyboard I have ever used. And that's coming from someone who used ThinkPads (I had the 770, the T42p, and the T60p) before switching to MacBooks, and who uses a Model M daily while at my desk. :-P
3. I have the base-model Surface Book. It's only a dual-core i5. But, again, I'm fine with that. The CPU is also housed in the screen, since the screen is made to be detachable from the keyboard. And since I have the base-model, I don't have the dGPU in my keyboard base either. So the base of the laptop stays cool while I use it on my lap. Oh...did I mention that the entire device (both keyboard base and screen) on the non-dGPU model is fanless? So no moving parts in the entire thing, noise-free, and isn't constantly sucking dust from the surrounding environment into itself.
4. There is a battery in both the screen and the keyboard base. Combined, I get amazing battery life, easily 8 hours or more depending. (I use it in laptop-mode 90% of the time.)
5. Screen on this is fantastic. Higher DPI than my 15" Retina MacBook Pro from 2012, way brighter, and the backlighting is more even. (I have the Samsung LCD on my 2012 rMBP...the model that never developed "image retention". I think the SB2 panel is made by Panasonic.)
6. It's got 2 USB-A, 1 USB-C (sadly no Thunderbolt, but it can handle DisplayPort), and a full-size SD.
7. Repairability is one area where it really falls flat, and in even bigger ways than the past MacBooks I own. :-( This thing I think got a repairability index of 1 (out of 10) from iFixIt. It's a sealed box for all intents and purposes. What really pisses me off, though, is that the SSD is not soldered onto the mainboard (it's a standard M.2 module), but there is absolutely no way of accessing it without basically destroying the computer in the process. If there was ONE area where I wish Microsoft had NOT taken any cues from Apple...gah, don't get me started. (And even then, at least with pre-2016 MacBook Pros, you could take the bottom cover off and get at the storage module in an emergency.)
8. The particular model I purchased ranges from $1,100 - 1,500 USD depending (list price is 1,500 but it's usually on sale). Don't know how that translates to your specific market.
9. I have not tried to use "desktop" Linux on it. I have booted SystemRescueCD off of a USB flash drive, though, in order to make a bit-for-bit image of my current Windows installation, and that worked fine (though to be fair I never bothered to start up X11). My understanding is that a lot of the hardware is supported even on current models; you can check out https://www.reddit.com/r/SurfaceLinux/comments/7kazwp/curren... for more details.
Anyway, just FYI.