Except 2 of them are a little indisposed towards growing up...
That said, I feel that while Pyrrha looks even more beautiful than her younger self, her expression makes me wanna cry.
Jaune... I wanna know what on earth happened to that kid lol.
Ruby looks like she made her scythe rifle get an upgrade, though I'm not sure what. At first I thought you made it so that the gun separates from the staff part so that she can shoot and beat up people simultaneously, but then I noticed the barrel attachment-looking thing and now I'm thinking that she's actually holding an augment- like she's modified it so that her staff can be put on her gun to change it from gun to rifle, or detach to be used as a staff? I dunno, I'd like your comment if you have the time. I'm actually intensely interested in this part, if you can't tell.
Penny, on the other hand, looks like some sort of cyber version of a standard RPG barmaid. Not bad, but I must admit that compared to the level of detail in the other 3 I'm feeling like something is missing. Where are her swords? Does she still use swords? She doesn't look like she's meant for battle, which raises the question of why she was rebuilt-/overhauled to be a more civilian mech.
So overall impression:
Your level of detail is fantastic in Pyrrha and Ruby's pictures. Jaune has great detail, but it feels like there's too much to me. Just my opinion though, it's never a truly bad thing to have a lot of detail- shows that you had a specific outcome in mind, either from the get-go, or as you brought him to light. Again, Penny looks great, but I feel something's... missing. I stated that her weapons were missing, and you might be wondering why I didn't mention Pyrrha's missing weapons - that's because in a throne-like picture like this, it can make sense at times not to be wearing the battle regalia, especially looking at her almost royal/wedding style dress. Actually, I just determined why I feel something's missing in Penny's frame- it's the lack of detail level. See, in Pyrrha's pic we have a stunning outfit and facial detail - seriously, she's making me sad with those puppy eyes - and the detail of the background. Jaune himself is overloaded with detail, and his very cape is his background so there's no end to the detail while still providing a simpler backdrop to his detailed armor and cyborg-ish appearance. Ruby is simply stunning in her outfit, and I like her in long hair, and the detail on her weapon is great though I will restate that I'm confused as to how you envision it in it's complete form overall. But then we have Penny- her outfit is mostly black, green and white against a relatively plain black background. She's practically being absorbed by her background, she's wearing a rather simple outfit, and considering where the series left off, fans like me will want to see with more detail what you yourself envision her to be. See, unlike Pyrrha which you get this profound state of sadness, there's not much emotion playing on Penny's face- when she was so bubbly and emotional before. Unlike with Jaune, where you clearly see that he's become a militarized sort of person, all we see here is what looks like a barmaid. I do see what hints to be the handle of the hilt of a blade, but I might be incorrect, and even if I'm not, I feel that was a wasted opportunity to show off her doubtlessly upgraded capabilities and weaponry.
The problem with pieces regarding an artist's vision for the future of some characters out of a show or book or game is that fans will want as much detail as possible, ranging from whether the character is happy with their future self, whether the character has changed their preferred set of equipment or stuck with it, hints on whether the character met with some drastically life-changing event, and more. Regarding equipment, if the show/book/game/movie they come from was heavily based on fighting, then fans will want to see exactly what their new weapons are, what they do, etc.
Overall, you nailed the state of emotion on the Pyrrha picture, the evidence of a clearly life-changing event with Jaune, the innovation of one's equipment with Ruby. Spot on for those three. If you could comment with detail on your thought process regarding Ruby's weapon, Jaune's state, and Penny's... well, everything, I'd vastly appreciate it.
Vision: You definitely had a concrete vision for the first 3. Splendid. I deduct one star for now simply because of Penny. (sorry :3)
Originality: While this may be based off of someone else's characters, there is so much done here that was solely the product of your mind that I believe this deserves 5/5 stars.
Technique: The only reason I deducted half a star is that I have a pet-peeve when it comes to lens flares. I dislike them. There's also the topic of Penny, again, but frankly something like this can happen so often and you did so darn well with the other 3 that I put it at half a star.
Impact: If a picture can make me want to write a 923 word essay that borders on thesis statement, your work has a fantastic level of impact and clearly stirs both emotion and imagination. Not to mention curiosity~ 5/5