Building a gaming pc with 4770k is a waste of $100+, and the overclocking ability of various mini itx boards is unlikely to vary much. Board features and quality would be far more important IMHO.
In fact, If I was building a smallish form factor games rig, I would use an i5 4430 or 4440, because with a single graphics card the performance is identical. And the arctic alpine R2 95 watt cooler costs ah heck all and runs quite as a mouse.