I googled quicky and from what I read, the Pico-ITX Epia board has a single 12v input. how many amps does it draw?
the M1-ATX is not powerful enough for your proposed system. the M1-ATX can provide 2A@12v and 10A@5v. your 3.5" HDD will draw up to 2A by itself which would max out the M1-ATX.
the M2-ATX-HV is the same price and can provide 7A@12v and 6A@5v. it should be able to handle your system with plenty of power to spare.