I really don't like Lin myself. She's something of a Boring Invincible Villain.
I'll try to explain myself better. See, we get into this game as a Pokemon trainer who has decided to face the Reborn League. Reborn is an unliveable hellhole that produced some of the most broken, defeated examples of humanity in the Poke-Earth, and it is under the yoke of Team Meteor, a ruthless terrorist organization that keeps it in the miserable state we see it in the beginning.
However, through our actions, and with the aid of the various characters we meet during our journey, things start slowly getting better. People begin to gain hope. They start to shake themselves out of their apathy, and to realize that there IS a chance for something better, and that it IS worth fighting for it. Team Meteor begins to lose ground, and the city starts to heal. By the time Episode 16 rolls, Reborn has become a much better place, and it is partly thanks to our actions. We get a feeling of hope, see what I'm saying?
But then comes Lin.
Nothing we do seems to even give her pause. Everything we do, it's all "just as planned" to her, and she's always five steps ahead of us. She can predict our moves and counter them as if she could see the future, and from what we've seen of her Pokemon, she's practically invincible in a Pokemon battle as well. It feels like the only reason we've gotten this far is because she wanted to amuse herself by watching us insects and our pathetic efforts to oppose her, and that if she wanted, she could wipe us out in two seconds flat. We've done nothing but play in her hands the whole time.
At this point (to me, at least), she has become something like Aizen or Yhwach (from Bleach), Madara (from Naruto), Esdeath (from Akame ga Kill) or Paul (from the Pokemon anime) - that is, she is such a credible threat that now, there doesn't seem to be any plausible way to beat her.
By contrast, I can think of Madame X, the main villainess of Pokemon Rejuvenation. While she is certainly powerful and dangerous, she doesn't have the same aura of invincibility that Lin projects, since she has suffered some defeats and setbacks that she didn't plan for.
That's my two cents at least.