It would be hard to do much with a pc that had no graphic output. Even installing an os and other things unless you had a way of running an auto installer or something. How would you know what settings you're altering, any message screens that pop up etc? Unless maybe running it with remote terminal and even then it's usually done once windows is set up which it would be infinitely easier to do with a monitor attached. I'd say get a gpu, even a cheap one. Something to output display.
Hd 5450's are still selling for less than $20 in the u.s. No there won't be any x99 motherboards with a display header/port because none of the cpu's for the 2011v3 socket feature integrated graphics. I'm sure they figure if you have $1000 for a cpu you probably have $20-30 for a graphics card.