I will say that linux has amazingly improved. I haven't had a single problem with my t440s wrt wifi or displays. NetworkManager for wifi and xrandr --auto for displays.. and I'm good to go. Even my thinkpad dock has been working perfectly.
And of course, the thinkpad keyboards are damned nice.
When was the last time you used a linux laptop? Because it doesn't sound recent (within 2 years)
Just in defense of Windows, which I happily use as both a developer and designer -- the latest versions (Windows 7 or 8) are pretty good at doing the two things you've described. If anything I have had many more problems diagnosing the Internet connections of friends' Macbooks.
And with managing external monitors, Windows has a keyboard shortcut to easily switch, plus it remembers screen configurations. Example: I have external monitors at home and at work. At home my monitor is to the top-left of my laptop screen. At work it's directly to the right. Whenever I hook up the HDMI or Mini Displayport it remembers which is which and automatically switches for me.
I would agree that Macbook Airs are great hardware, but the Windows ecosystem is catching up pretty fast too. Some of the new ultrabooks are really nice -- give them a shot at least.
From which year is the distro you are using on your linux box?
--------------------------------------------------------- To answer OP question, from my personal experience the ASUS Zenbook is a good choice:
http://www.asus.com/us/Notebooks_Ultrabooks/ASUS_ZENBOOK_UX3...
And the review :
I was very disappointed with the multi-monitor support on Mac. Some apps takeover both monitors while others don't, and maximizing/docking windows left/right was just tedious. Windows nails multi-monitor support, even remembering the display configuration based on which external monitor is plugged in.
Not having Linux is annoying because cygwin is pretty terrible, but I just SSH into a remote linux server or local vm.
1. Have you tried full screen in 10.9? Seems to have improved things a bit, though it's definitely a work in progress.
2. Which SSH client do you use? I'm considering getting a Surface 3 Pro, but the lack of a proper terminal like Terminal.app or Gnome Terminal makes me skittish. PuTTY is...okay. (The alternative would be to get a 13" rMBP to replace the one I'm returning to my soon-former employer this week.)
2. I use KiTTY, a PuTTY port with a few extra features. It's not amazing but is decent after some configuration.
I've used and supported many Windows laptops. Changing wifi networks and external monitors both work great. For the former, I'm not even sure what issue you've encountered; I just select a network and, if needed, type in a key, and it just works.
One important part here is that it must be able to adapt quickly and easily to the different environment, meaning, network connections, external screens (retroprojectors), etc.
Honestly, the only kind of laptop/system that can do that, are MacOSX Apple laptops. I'm afraid I must say that even with Linux you will often have difficulties to connect to the random WIFI setups you'll find, or to manage the external monitors, etc (and I won't even mention MS-Windows, what a joke).
Oh, and there's also the battery life, 8+ or 10+ hours...
I mean, my main workstation is a Linux box, but as laptop, I use a MacBookAir, because when you're on battery you don't want to lose half an hour of battery time connecting to the network (or losing half the times the hibernation state).
As for keyboard, well, it's laptop keyboard anyways. When working at home, just hook a DasKeyboard or a Filco Otaku on the USB port.
Given your need in pixels, you'd want a MacBook Pro Retina. http://www.apple.com/macbook-pro/specs-retina/
I've worked recently for a year with a Dell laptop with various linux distributions on it (mainly at first ubuntu, but later I switched to debian) and it was quite decent (very nice screen and processor), however it still had those little problem with hibernation, external screens from time to time, switching wifi setups was horrible, and battery time (not mentionning the heat). (On the other hand, I must say that ubuntu works well on a little netbook computer I have around, but of course, I don't ask as much of it as of a development computer (come to think of it, it still had quite a difficult time with a GSM dongle)).
No, really, if you want to be productive with your laptop, use a Mac one.