You have a pretty short inseam. I would stick with the 170s. I would also be worried about being able to get low enough with 700c wheels with your height and inseam. Maybe yes, maybe no. Give that some very serious thought.
I wouldn’t bother with the DA cassettes for anything but hilly races. Uses ultegra otherwise.
It is all about fit. The 650 wheels may be necessary to get a good aero position. They may not. It depends on the bike and how aggressive you want to get.
Nothing wrong with DA cassettes, just that they are expensive. Their only advantage is weight.