One thing I've noticed after using a smartwatch for a bit now is that the ambient watch face is way more important to me than the active watch face. When I'm looking for other watch faces to try, the most important thing to me is how it looks in ambient mode, because that's what the thing will look like 90% of the day. The active watch face gets about zero use from me, because if my smartwatch is being used it means I'm looking at notification cards or replying to texts/emails.
I find this interesting because it seems like many watch face designers put so much emphasis on the active watch face and often neglect the ambient mode, when in reality the active watch face gets so little view time compared to the ambient one.
Also tying into this is the realization that AMOLED is 100% the way to go. The Moto 360's ambient watch faces look pretty bad compared to Huawei's ambient watch faces.