To reply to myself, yeah, Google Flights UI leaves a lot to be desired vs Hipmunk. The visualization of flights and layovers on Hipmunk is vastly better.

I like how prominent Google Flights makes the layovers in text form, but it's not visual, and you can't sort by agony.

These days I pretty much only fly nonstop or the shortest possible route if a layover is absolutely necessary. Looking at flights right now, the cheapest flight SFO-Frankfurt is 15h of travel and goes through Dallas (!!) vs 10h of travel for the nonstop. No-brainer, especially when you factor in getting on and off the planes, the risk of missed connections, etc.

I think Hipmunk wastes a tremendous amount of space, in a project timeline type view that is just plain unnecessary. Google Flights, is a simple list, with filters, and it's fast. The calendar view with the pricing is ridiculously helpful.