It's questionable how old to make her look if she's going to be thousands of years old.
That's her origin, she's an immortal much like Marvel's Thor, you are not going to find a teen-aged Thor in a modern High School.
But seriously?
How does a new (or very, very old) nation present itself to the world?
The White house or the UN?
Possibly show up with a couple bottles of wine for kathy lee and Hoda on the fourth hour of the Today show?
What's her message?
"peace"?
"calm down"?
In the 40s it was all about the Nazis, which almost made sense.
I find nothing wrong with her World War II origins, a downed fighter pilot crashes on a mysterious uncharted island full of Amazons, that is the standard origin for Wonder Woman.
Post crisis In the 80s the "peace" thing was code for "holy shit atomic weapons are scary".
That's politics, Wonder Woman is a crime fighter, not a negotiator.
She needs a voice and an audience.
Surely if she wanted to promote peace and stop war, then she should go to a warzone?
I just think Wonder Woman is not a suitable character for a high school small town setting, there is a character very much what they are trying to make her out to be and that's Supergirl. They had a supergirl in smallville, so why not a series about her? They start with Wonder Woman and try to reinvent her so that she is no longer reconnizable to her established audience base. Why fit a square peg in a round hole when there it a round peg ready made that already fits?