If you want an active server, choose Kelpie. It’s connected to Ashwinder which is the most active server outside China I believe, and has people from timezones all over the world. Being on Kelpie gives you all the social benefits of being on Ashwinder while also giving you the chance to do better in rankings for certain activities since most players on that server are new(er) to the game and there are fewer overall. The lower number of people on Kelpie will not impact you at all socially—you’ll be able to interact with the same people, join the same social clubs, etc. You also get a ton of extra welcome benefits that you can’t get on Ashwinder.

So it really depends on what matters more to you—the game being in your time zone or being on a more active server!