I love the idea of a black and white (or navy and white) patterned shoe for you, or a spectator style. It would work brilliantly with the simplicity of the blue and white palette. (And you know, I am never going to be the one complaining about blue and white, especially in summer!) I really like your uniform. It appeals to me and it does not seem boring because you keep the variety with changes of silhouette.
Red shoes would also be great.
Too bad about those Paul Greens -- they'd be perfect. But crossing fingers on the loafers.
I love you in the dress, and agree that more dresses of that kind are worth seeking for work. I have made a sort of goal to buy one summer dress per year. I don't work in an office so the dresses I am purchasing are more casual (so probably easier to find) but at the same time, I don't want spaghetti straps and the like -- they can't be "beachwear" kind of dresses for me. Anyway, there's nothing cooler or fresher or easier to wear in summer.