First off, that “criticism” makes zero sense to me.
People sure are quick to criticize stuff.
It’s not like Tevua is 100% of the route. It’s only like half of it. And the other half is about a girl making her dream come true: to start dating the boy she was in love with ever since the first time they’ve met. How is that not Character-oriented?
Now back to the Tevua arc.
Sure, the two of them are caught up in something huge and reacting is the only thing they can do.
But even that is only what happens “on the surface”. And once you use your brain (and knowledge from Refrain) and get to the depths of things, you’ll see that it’s pretty much purely character-oriented.
In the first place, the “correct” answer is the obviously wrong one if you use common sense. The smarter choice gets you to the Bad ending. There’s a civil war going on in Kud’s home country, so returning there literally means risking your life. But you have to choose that because otherwise Kud will not get rid of her regrets. You’re making a choice that’ll affect the (worst case short) rest of your life based on what’s important for the character.
Why? Because Kud regretted not going to her mother’s side earlier because she’s afraid of facing her AND she’s getting along with Riki, so she’d rather not leave his side again.
Also, everything that happens after Kud leaves the school is a metaphor on her regrets.
All that imprisonment and being used as a sacrifice. These things are happening because Kud (subconsciously) wants them to. She sees herself as a “useless gear” that failed to become nearly as awesome as her mom and was afraid to face her. So if she could die on her mom’s stead and calm down rioting people just a bit by becoming a sacrifice, then she’s totally fine with that.
The cave and the chains she’s bound with symbolize her regrets that mentally bind her. So overcoming those regrets is visualized by shattering the chains with the “useless gear”.
I’ve written this stuff in more detail here (possible refrain spoilers): http://pastebin.com/3wHCEi4s
(It happened soon after completing refrain, during a chat with a friend, and said friend uploaded it like that.)
For better insight in her route and character concept, you should research the terms “Sputnik” and “Kudryavka”/“Laika”
…so I really don’t see how this route could be not character-oriented at all o.O