I can’t say I have played enough during both closed beta and stress test, but it feels like winning by controlling sacred sites takes to much effort and risk in comparison with other ways.
An average game lasts about 25-30 mins. Holding all sacred sites for 10 mins means that you need to hold all points continuously for a major part of a game. And if the control is lost for a brief period and then regained the countdown starts again.
In addition winning through sacred sites doesn’t differ mechanically from winning through a wonder. When going for a win through a wonder players build their “own sacred site” and hold it for 10 mins continuously
I would suggest the following change: A player (or a team) wins if all sacred sites are controlled 10 mins in total (not continuously). So, when the control over sites is lost, the timer freezes, and when the control is regained countdown continues.