good indicators are:
- will you buy an unlocked CPU or not? (Z170 or H110-170)
- would you like to have the option for SLI/CF in the future
- looks, basically if you are doing a build with matching components or have a case with a window you want the right color for the mobo.
*the rest are pretty much the same features with I think the most important is choosing a motherboard with a Intel LAN controller.