It's not whether Alain has won or lost that bothers me, it's his overall character, I guess.
He's an adult, but he's naive. He cares for his Charizard to the point that it took until the finals for his other Pokémon to be seen... It's pretty minor stuff, but it makes it hard to be interested in him.
It's probably just me though...
He's a bit naive, though that's more because he does let his passion and emotions sometime get the better of him. He tries acting like Mr. Stoic but in actuality his goals are ambition driven (and if anything he has a more obtainable goal than "I want to be a Pokemon Master"). Why does he just use a Charizard (that can Mega Evolve into MCX)? We've seen in flashbacks that Charmander was either his Starter or he got close to the one Professor Sycamore was studying. He went on a journey to help Sycamore learn about Mega Evolution and decided the best way to do so was battling with and against Mega Pokemon. However Mega Stones are difficult to obtain, it's only from Lysandre's intervention did he get both his Key Stone and Charizardite X (which is another factor of itself we'll cover). So it's more than him wanting to win with just MCX but rather he feels he has an obligation to his mentors and doesn't want to disappoint them.
Going back to Lysandre, not only does Alain have loyalties to Sycamore but as well as to Lysandre. During his journey it was Lysandre who sort of picked up being the mentor figure to Alain, giving him the Key Stone, Charizardite X, and as well missions and objectives relating to Mega Evolution. Lysandre has sort of provided Alain with some guidance, though Alain still does what he wants he's perfectly willing to go on missions for Lysandre. Of course Alain didn't know anything about Team Flare at the beginning, he thought Lysandre just wanted to study Mega Evolution like Sycamore but then also use it (Lysandre is a businessman afterall).
The naivety comes back into play here because one thing you have to remember about Lysandre is that he's suppose to be a manipulator, he attracts thousands to his cause (which they need to give him millions to join) including a member of the Elite Four (and a newscaster so he can easily hide Flare's activities from the public); even Sycamore said he was a bit taken away from Lysandre's passion. So Alain is being manipulated by Lysandre, however I don't feel its because Lysandre think he's a complete, on the contrary, seems like Lysandre considers a person of interest even informing him of Team Flare without forcing him to join (maybe as a trial). Alain is being set up to be Lysandre's dragon (insert your on Mega Charizard X joke here).
But back to Alain, all that is admittedly contextual as we don't really see him act differently to Sycamore or Lysandre, how about we talk about one of Alain's most emotionally tense moments and a reason why he may not be more easily controlled by Lysandre. Mairin and Chespie started as unwanted tag-alongs but they became friends with Alain over due time (and Mairin helping to save Alain helped too). However this just meant Alain wants to protect them, and being Mr. Stoic decides the best way to persaude them to stop following him on his more dangerous journey is to push them away. Next thing Alain knows, Chespie is in a coma and Mairin is heart-broken. Alain storms off with a glare in his eyes, not because he's angry at anyone else, but because he's angry at himself. He blames himself for pushing Mairin away which led to Chespie's accident (unaware Lysandre was doing some insidious stuff). He vows to cure Chespie and have Mairin smile again, all making it more easier for Lysandre to manipulate him as Lysandre knows what's truly going on thus the only one who knows how to cure Chespie. Cue Alain then helping Team Flare capture Z2 with no qualms.
I'm sure Alain is going to win. Personally it just doesn't feel right for Ash to win outside of the Kanto/Johto League, especially in a foreign region. I still argue Ash becoming a Kanto Frontier Brain is the best ending for him, the unique battling rules match his style and its in his home region (not to mention he won it and Scott offered him the job which is still open). But outside of that, Alain is not only from Kalos but he's shown to be just as strong as Ash is (Ash's Kalos team is one of his strongest teams, rivaling his Sinnoh Team; not to mention he has Greninja with its pseudo-Mega evolution ability) but more competent, is working with the villain team whose plans have yet to begun, and due to the emotional baggage has more ambition to win. It would also set up Alain's dragon status, as when they need to stop Team Flare that would make Alain one of Ash's biggest threats (and then biggest ally one he snaps to his senses).
So one must then wonder how Alain is going to get out of Lysandre's control. Well before we make any prediction we got to know what the anime is planning. Is Lysandre going to follow his game counterpart's plan (immortality for Team Flare + genocide for everyone else; I think Alain might have a small problem with that plan (especially if its revealed that though Lysandre would want Alain part of his new world, Mairin probably would be in the second part of that plan)) or are they going somewhere different (which if they do they can make it so Lysandre's plan is less extreme thus not much rejection from Alain so it would be up to Ash & co. (and probably also Mairin) to snap him out of it).