I enjoyed the simplicity of the style, though some texture on the fully blue landscape would help convey "motion" when panning the camera. The unit controls seemed decent but could be improved still I think -- having selection indicators would definitely help.
As for the RTSness, I wasn't really sure where to go initially. I saw an infinite blue ocean and my units were autospawning so I sort of just camped out. After a bit of time I saw that enemies were coming for the top-right of the map so I began going to combat them. I got absolutely destroyed by the enemy units!! I had a tough time knowing how to be better than the opponent :O
I believe the game needs some controls for choosing which units I'm building or at least a means of balancing between unit construction and economy collection. Currently, the player has little agency over the base-building portion of the game.
Ok whew, long feedback but I wanted to share it :)