it really is a big topic when I research for my article here.
Given the highspeed Internet you have and your expectation to utilize the full strength of it (reminder: usually ISP promises at top 80% of it), for "future proof" say 5 years, you may want to consider the following features:
802.11ac @ 160MHz (discontiguous)
Router class at least AC3100 to give you minimum 1000Mbps on either 2.4/5GHz channel
at least simultaneous dual band, so you can group slower clients on one band to attain max speed on the other band.