[Android Q&A, Help & Troubleshooting] TFGBD:
Now I'm curious. How did you get KVM working on your Rasberry Pi 3 B+? I compiled QEMU from source using a modification of your instructions and couldn't get QEMU to even start with KVM enabled. What Linux distro are you using on the Pi? What linux did you use as your guest image? What was your exact qemu command line?

I wouldn't expect the ARM Windows 10 laptops to run any Linux yet. They're too new. We may need to wait years. The Windows RT devices were just secure boot unlocked a few months ago by someone from here and they still can't run any Linux.

Honestly, you probably are just better off getting a Zenfone 2. With the kernel mod, x86 Windows pretty much "just works." I just wish QEMU had a virtual battery meter so the VM could hibernate when the phone's battery gets low.

As an aside, I have a few Atom Baytrail Windows tablets that are quite similar to Android models and it's quite amazing what I can do with them out of the box when compared to Android. A few of them have virtualization enabled out of the box so all I need to do to use a VM is install VMWare, Virtualbox, Virtual PC, etc. and it "just works". No hacking, no flashing custom kernels, no command line tools at all. I've attached a picture of my Nextbook NXW8QC16G running Windows XP in VMWare and showing virtualization enabled in the task manager. The other picture is running Windows Server 2012R2, a 64-bit guest OS.

Your mention of virtio gives me an idea: Isn't it possible we can compile the virtio graphics driver for AARCH64 and somehow inject it in our ARM64 Windows image? If we did that, would Windows then be able to be used with ARM64 KVM acceleration? That guy who made the ARM64 Windows QEMU blog post already compiled the virtio disk drivers for AARCH64 and was able to get the installer to install to a virtual hard drive. Maybe all we need are ARM Windows compiled drivers for the rest of QEMU's special emulated hardware. I use the x86 Windows QXL driver with Windows 8.1 on my Zenfone 2 and it seems to work. Though, I had to boot with the VGA video mode first and install it via device manager manually.

Also, if you want an NT based OS on emulated x86 on ARM, have you thought of trying something older than XP like Windows NT 3.51 or 4.0? These were designed for 386/486s so should be more usable on emulated x86 QEMU than something like Windows XP. Office 97 works on Windows NT 3.51 and Office 2000 and maybe even XP and 2002 will work on NT 4.0. Softmaker Office 2008 also works somewhat on NT 3.51. Obviously Windows 98 may also be faster but it sounds like you prefer NT so these may be an option. If you install Windows NT 4.0 Terminal Server Edition, you will even be able to RDP into your emulated machines. Windows NT 3.51 also has an optional edition with remote, multiuser support called Citrix Winframe but I was unable to find an Android Citrix client that can still connect to it. (they're all too new)

I think we're starting to see the limitation of devices marketed as "phones" They're not an open computing platform or standard like the PC or even Macs.

We really need some kind of open standard firmware for phones like the UEFI/BIOS on PCs and an OS to go with it. It would be great if there were some kind of "open", generic (not neccessarily open source) OS that let you install drivers after being installed like Windows. Android is sort of open but not the hardware and good luck buying a device that will have an unlocked bootloader and get custom ROMs. Plus, you can't run anything other than Android and maybe another linux if you are lucky. I dunno, it scares me that these phones may become the defacto computing platform when they are so closed and proprietairy. At least with a PC, I know I can install the latest OS and be up to date for at least 15+ years if I want to be. We need that for phones but it just doesn't exist yet.