Seems quite clear on my phone. I might tone down the orange a bit to separate it better from the yellow.
(Edited - the new darker colour works better I think. Perhaps a white rather than a black border to pick it up from the map?)
Inspired by the Tabletop Simulator mod, I’ve 3d-printed city, tower and farm pieces for my set in faction colours, which I find makes it much easier to read the board. If like me you’re rubbish at art, I recommend https://game-icons.net/ .