Agree with 350 in principle that a hub is great for flat terrain. Problem with your frame is that it's aluminum which means one or two torque arms for a rear hub or use a front hub if the fork is steel. Just for information, I built a 750w BBS02 mid drive with a 52V battery ($500 for motor kit, $320 for 52V, 10ah Samsung battery) and it was only slightly more difficult than front and rear hub conversions, just needed some bike tools that I already had.