Do you plan on running panniers? If so you really need to take heel clearance into consideration. Nothing is more infuriating while touring than having your heel smack the front of the pannier every pedal stroke. From you photo, it doesn't look like you will have enough.
And I may a Luddite when it comes to these things, but the racks that are going to subject to shock load and vibration while carrying all your stuff is not where I would look to save weight. I want those things strong. Welded aluminum tube all the way. There should be no discernible flex when loaded. Flex will break things.