No need to spend the extra money on X370 boards imho. Here's some of the best B350 boards that come with many features and have awesome BIOS.
MSI B350 Tomahawk
Gigabyte AB350 - Gaming 3 (does not let you raise the CPU BCLK, 5 4-pin)
ASUS Prime B350 - Plus
ASRock B350 Pro4 (to my knowledge, this has the best BIOS out of the bunch)