Sylveon
I absolutely love Sylveon! :) In short, I'd say she's pretty much the textbook definition of adorable <3 It just feels like everything sweet, joyful, and endearing was incorporated into her design; those adorable colors, her cute bows and ribbons, just amazing <3 She's definitely one of my absolute fave Pokémon, and one of the best things to come out of the new Fairy type. I never really started playing my Y version until last October, and I caught my Eevee a couple months after (a critical capture, no less!), which I named Sylver, and is now my precious Sylveon :) He's pretty powerful and bulky, and he's proved to be very useful in my playthrough, and he's been there at the big story parts; I plan to have him as part of my Elite Four team :)
Overall, Sylveon ranks as my second favorite Eeveelution, behind Leafeon; the ones after Sylveon being Glaceon, Eevee, Umbreon, Vaporeon, Espeon, Flareon , and Jolteon in that order. (Now, I really like all of them, and think they're all adorable, but some are just moreso to me :P)
Sylveon seems pretty decent competitively too; it's got a good ability, and a lot of Sp. Attack and bulk to it; plus, special attackers are my favorite. As for her evolution method, I don't mind at all. Amie is something I've been happily occupied with quite often (I've always been really into the "people's spiritual/emotional bond with Pokémon" thing), so it was easy for me to get Sylveon. I really hope that it's a feature that stays in future games. And even if it doesn't, they'll definitely make an alternative method for evolving Eevee into Sylveon. I'm currently making my way through the current series anime (subs!), and while I'm quite a ways behind, I'm excited to see Serena's adorable Eevee evolve. <3
Cherrim
Not much for me to say about this one either, but I absolutely adore the Sunshine form! It's just so happy and cute! :3 Other than seeing it every now and then in the games and the brief appearance of a
few happy Cherrim in the Darkrai movie, I don't remember much of this guy. But it's definitely marked down as one of the cutest mons, in my opinion. It may not be the most powerful Pokémon, but in my free time, I think I'll consider getting Cherrim in AS. ^^
Chandelure
I remember this guy a bit more fondly, but never really had much of an opinion of him until lately. I don't remember using one in BW, and I haven't used one in XY/ORAS. I remember
its appearance in Smash Bros, in which it actually absorbed Fire-based attacks and made itself more powerful- a nice attention to detail there. I recently learned that it's a Special Attacking
beast, so that prompts me to train up a Litwick someday (which really helps as I love Litwick <3). I really do like its design and typing (always been fond of Fire types), and the Fire-absorbing abilities, it's really useful.
I think it's awesome that it's in Pokkén. Really goes to show that there's no limits as to what can make the roster, and I'm really interested to see how they'll make it work. And just look at
its gorgeous artwork! So much detail.
Like it or not, it seems that this guy's been getting a nice amount of attention lately, particularly from the unexpected appearances like Smash and Pokkén. I'm happy for this dude, he's a cool Pokémon, and I wouldn't mind seeing him continue getting this kind of love in the future :)
I was a little disappointed that a Pokémon like Chandelure was included in the game. I mean, they had much better Pokémon to choose from with greater potential, like Mienshao, Braviary, Bisharp, or GOLURK.
I don't necessarily think the inclusion of him rules out any of those other Pokémon being in the game, as well. They're still gonna be adding new ones for a while, I'd think.