Get EasyBCD and add the vhd image to the boot list. check the second half of windows8geek. com/2011/04/install-windows-8-in-a-virtual-machine-bootable-vhd/ for more details.
You can also use Windows Virtual PC (the one for windows 7), Install Windows 8 that way (uses VHD), on reboot it will BSOD every time (in the virtual machine), stop at this point, use EasyBCD to easily add the VHD as boot entry, reboot, now you have a nearly fully installed VHD that finalizes itself, you won't be able to use it inside of Virtual PC, these builds don't like virtual machines, reason it crashes after setup This is just another way of 'creating' a VHD, it's a little better as you can use your windows while it installs, so once your boot into the vhd it only takes some minutes until your desktop
honestly, the install.wim -> .vhd method described in the article is pretty quick. when you boot to the vhd it's already transferred the files to set up the system, so there's no wait time there. not knocking your method, just my opinion here.
i Think that can be also useful this program that give a GUI to ImageX autoitscript. com/site/autoit-tools/gimagex/