Ella is complex because her actions can be interpreted in many ways and we don't know her ultimate goal.
I think it's pretty clear that she's not some good samaritan, but can we really categorize her as a villain?
Take for example Grand Admiral Thrawn from Star Wars (book version).
Or Revan, if you're more of a gamer than a reader.
At first glance, they were cruel conquerors and dictators who killed millions of people.
But they both wanted practically the same thing.
A catastrophe of enormous proportions was approaching, and unless something was done, virtually all life in the entire galaxy could be destroyed. The leaders of the planets were disunited, corrupt, and motivated by self-interest. The republic was not united and democracy worked too slowly and unreliably. The galaxy needed to be united, by force if it had to be, and a capable leader who could make quick and effective decisions needed to be put at the helm. That was the only way to have hope of survival. Both were actually martyrs, willing to take on the mantle of a cruel dictator just so they could save everyone.
For the same reason, I refuse to classify Ella as a villain.
We don't have enough information for that. We still don't know what her goal is. We know that she has no problem killing people, but we also know that she doesn't kill for no reason and doesn't cause more suffering than she has to. Can such behavior be justified by the nobility of her goal? Time will tell...
Ya I love Ella, she's only ever helped us. She does some terrible shit to other people but if I don't know them I don't really care. And while her methods would be questionable to regular humans we aren't that are we. We can't just go to the gym and get experience by working out, or sign up at our local superhuman WWE, so her making life threatening scenarios not only adjusted our mindset to that kind of world, but also physically prepared us for it as well.
I'll always say it but she has soft sides to herself and those around her. Could she have absolutely obliterated everyone at the beach? Sure. Did she? No, so at least she's not PURE senseless evil. Did she have to run an orphanage, no. Or be part of a band? Nah. Did she have to help us along, the multiple end deads say no. Warn us about various topics? Nadda.
If we were a normal human it would be like a Mafia boss sending gunmen to your house to prep you for the life style every other week. But we aren't human, and our power isn't exactly injury heavy we aren't going to be in a coma for the weekend if we get a booboo on our kneecap, plus the monsters or even other superhumans aren't going to wait for you to get a band aid either.
Her methods are harsh, cruel, and morally questionable. But also efficient, realistic, and strengthening. I was never a Jake fan so I don't care what she did to him, we barely know Mia, and Deryl turned into a massive cunt towards the end of our fight showing jealousy like it was a god damn SMASH tournament, except burning us alive. In fact I honestly hope we get the option to keep the clone and eat the original just so I can say, "See, we're still equal and play fighting like we used to!" with a dumb fucking look on my face, his clone has been great!
A weird comparison but she's not dissimilar to one of those anime master that put you through LIFE THREATENING hell training but the MC comically chalks it up to, "This old man is crazy!" But in this case, we actually react realistically. She TECHNICALLY never kills a single one of your friends, even going so far as to heal Mia on a fucking whim when she didn't need to, she didn't even do that to Mia to begin with, that was due to Jake being fucking Jake. And speaking of, she doesn't kill Jake either, you do if you choose to, and if not; he got himself into that fucked up ending being a bloody regretful mess on the floor, Ella was only trying to toughen him up and use him occasionally. She hasn't killed Deryl either, she's using him too BUT he has powers now, which we know he deeply wanted, and chances are it'll be up to us again to do the "evil" part people love to blame Ella for. And then she also would've helped us with Klaus if I'm not mistaken, should we have asked but that's up for debate as she probably would've wanted to use the opportunity to train us.
There are people I hate SOOO much more than Ella if I'm honest, like Nicolette, Jake, Danica, NTR gang, prison pricks, Jared, Kenny, etc. Whenever Ella is on screen, I know I'm in for a good time, she gave us powers for god sake.