The results of a recent poll on 1v1 matchmaker maps are here:
Ideally new maps should not need to be deployed (for reference any map appearing in the campaign satisfies this, among others).
My initial take would be to replace Desert Needle, Barren and Vittra with something along the lines of:
* Calamity, Otago, or some other largeish map
* Iced Coffee or Dune Patrol, or some other smallish map
* Archers Valley or Obsidian
I'd like to see Gecko Isle stick around a little longer but Hide and Seek and Trojan Hills could go.