Not a major issue, but I sometimes find it hard to distinguish the towers of different players based on their colors. This is especially true for some architecture sets, such as the East Asian and Western European sets. Below is an example of what I mean, two of the towers are purple, two are blue.
This is not an issue at all for some other architecture sets, such as the Meso-American and South Asian sets.
Am I the only one, and if not, can this be improved?