Is it really that surprising though? We know that those who survive the infection at younger ages are typically the most gifted and she's a spawn of the 3rd Apostle. Ella was turned at 14 and probably reached her 3rd Evolution by 15, if she progressed similarly to the MC. So some time passed that in the 6 years leading up to the start of the game she's reached level 4 and remained there. She's 21 currently, maybe about to be 22. When laid out like that, it's impressive but not shocking with what we know.
She's also not exactly unique in that aspect, besides surviving the infection at a young age. Lexi, for example, was turned around the same time at 23 and became level 4 at an unknown amount of time before becoming level 5 at 28, currently. Both got infected 5 to 6 years ago(Ella 14 and Lexi 23) and both reached level 4, to now level 5, in that span of time(Ella 21 and Lexi 28 now).
The current ridiculous person is actually Henri, honestly. He skipped all the way to his 5th Evolution in a week on accident from level 1(?). We don't exactly know the time table from when he got infected to that event happening but we do know he reached it naturally and has been at it for some decades like Malik and Bernhardt.
All that said, MC's growth is still fast. It's been almost a year worth of time in game and he's already reached his 3rd level, though he did it "Artificially". With this update, we also learned that the 5th Evolution is extremely hard to reach naturally. Which would explain why everyone seems to get stuck at their 4th, and it keeps them there for years. Even Captains from HERO were stuck there until Xanthe developed the serum. That means people like Nyx, Zack and Lucius were level 4 for decades. Ella would've likely shared the same fate as well, if she didn't steal the serum.
So, while what Ella and the MC did was impressive, they're not the sole people progressing fast and it seems reasonable, in verse, when looking at characters like Lexi and so on.
Fuck I gotta pay attention, I totally forgot about Henri tho that's true he must REALLY have a deep connection with his Apostle source.
I do wonder about how Evolutions ACTUALLY work though. I mean it seems like there is a multitude of factors that can play into evolving, but the only one that is "questionable" is Xanthe's serum route.
So I believe from what I remember on how one Evolves is:
1. Pushing yourself to your limits, even to the brink of death.
-Source: Ella, Teacher, Xanthe.
-Examples: Alice Lvl 2
2. Allowing a "feeling" to overtake you? At the risk of monsterfying.
-Source: Ella, Xanthe.
-Examples: Henri? Lvl 1-5, MC (Almost)
3. Consuming monster material, at the risk of being overtaken.
-Source: Xanthe, The Eye (3rd&4th Arbiter)
-Examples: MC Lvl 3
4. Having help from your source Apostle and/or Arbiter.
-Source: The Eye (3rd&4th Arbiter)
-Examples: MC Lvl 2-3, Henri? Lvl 1-5
5. (Artificial) Xanthe's Serum, at the risk of your body not handling it only it seems (RIDICULOUSLY OP), and MAYBE severing your favoritism from your source Apostle and/or Arbiter.
-Source: Xanthe, Teacher
-Examples: Lexi Lvl 5, Ella Lvl 5, Clark Lvl 5, Nicolette Lvl 5, Lisa Lvl 5, Nyx? Lvl 5, Lucius? Lvl 5, etc. (Save for Malik, Bernhardt, and Henri)
6. (Artificial?) Rebis making.
-Source: Deryl, Del, Rebis Monster
-Examples: Deryl Lvl 1-3 (Rigged and STILL incomplete)
I don't know if you can just "wake up" one day and evolve so calling the MC's Evolvtion "Artificial" I don't think would be the right term, he did it naturally at the risk of being consumed by monster material, definitely not something you can do every Saturday night.
I do wonder if that's what makes Malik, Bernhardt, and Henri so strong; due to evolving "naturally" throughout their entire process as nature intended. It does make me wonder if Lvl 5 is a SELECTIVE evolution done through only the will of the superhuman's source Apostle or even Arbiter, much like the MC's favoritism by the 3rd&4th Arbiter. They can also speak monster, which makes me wonder if they are being groomed as allies? For when they descend on the Earth, rather than vessels for the Arbiters. Something tells me Malik or even Bernhardt wouldn't be very accepting of giving up their free will to be essentially a puppet, they like having their OWN power. Even if Bernhardt's goal aligned by culling the human populace or something, Malik FOR SURE wouldn't be on board with enslaving or even annihilating the human race.
So if we do go by that theory, what made Malik, this kind hearted individual favorited by a race that wants lives weaker than them gone? Or Bernhardt, who wants the SUPERHUMAN race rather than Monster race to thrive. We know Henri's was accidental, so maybe they just liked his nature or something to do with how he would react to scenarios presented in the future by their kind.
But even below Lvl 5 people seem to get "visions" from their monster parent and even their source Apostles like Alice, but I did notice Alice wasn't contacted by the Arbiter of her source pair, then again; she WASN'T turned by her source Apostle, much less by a pair of them like we were.
We do know CORRUPTION also plays a role, which is odd because Malik doesn't strike me as the type, and I'm not sure if Bernhardt is eating monsters, he seems to despise them too. But Ella for instance casually talks to the 3rd or 4th, while the MC also has dreams speaking to them. I think the crazy part about the MC in particular though is we don't JUST dream about our parent monsters, rather about monsters we haven't even seen before like Danica's or Oscar's.
I dunno, just thought I'd throw it all out there, lemme know if I missed anything.