Rather than additional new flashes I would like to get from Canon a reasonably priced (i.e. 49,- USD) RT-receiver for all existing slve-enabled EX-flashes ... 270 EX II, 320EX, 380EX, 430EX/II, 580EX/II.
Most of us already paid for Canon speedlites!
And Canon better go back to the drawing board and design a fully-specced ST-E3-RT Mk. II with a hologram laser-AF-illuminator ... for a reasonable 149,- USD.