So, just for fun, I compiled a "Report Card" examining how each Playable Series in Brawl has evolved between the gap between it and Smash 4, examining which series got a boost, which series sort of got a bit stale, and which series basically died off.
It'll be interesting to see if any series ends up reversing itself by the time of Smash 5 like quite a few did between Brawl and 4.
Winners
* Luigi: Got a fucking year named after him, complete with a Luigi's Mansion Sequel. It's safe to say he was the biggest winner here.
* Pit: A come-back story, went from a completely nobody to headlining one of the most ambitious 3DS Games, got a series of AR Cards, Anime tie-ins, and was featured as one of the initial characters for Smash 4, arguably replacing Yoshi's spot. Plus, well, Kid Icarus Uprising was an amazing game in my opinion, awkward controls be damned!
* Donkey Kong: The runner-up for "Most Improved", after years of being stuck in Spin-Off Hell, was revived in an extremely well-received game by notable developer Retro, and, now, is getting a sequel to that game which looks to be an improvement of the original in every way. Plus a pretty nice looking 3DS Remake too. Expand Dong, baby!
* Mario: Even though Mario is another "duh" choice, I think the gap between Brawl and 4 is his greatest ever, especially compared to 64-Brawl which only saw Sunshine, NSMB, and Galaxy as mainline games, the latter barely coming out before Brawl did, this time we got Galaxy 2, 3D Land, 3D World, and GOOD New Super Mario Brothers games. Bonus points awarded to Bowser, who brought back his Koopalings, became a powerful villain once more, and became playable again, as well as Peach, also recovering her playable status.
* Kirby: Brawl saw the addition of not one, but two new Kirby characters, and perhaps it was a sign of the good things to come, as Kirby finally got a main series console game after years of being placed on the back burner. Add to that a solid console spin-off with beautiful orchestrated music, a remake of Super Star, a fan favorite, and the Dream Collection released for his 25th, Kirby's doing great! And I've heard positive things about the 3DS Kirby as well.
* Pokemon: Not surprising, as it's always been a strong series (although perhaps some may see the games released between Melee and Brawl, RS and DP, as being the low point), but it got even stronger between Brawl and 4, with two new generations being released (and the solid Gen IV Platinum and HG/SS), the latter which finally brought the handheld series into the polygonal realm, and a slight resurgence in mainstream popularity in the West. However, the low amount of new Pokemon in Generation VI does beg the question...will the series keep this steam till the next Smash Brothers is released?
* Wario: Especially on the Wario Land side, where we finally got his classic games released on the 3DS E-Shop (one, unfortunately, only for Ambassadors at this point), and the visually beautiful, if a bit flawed, Wario Land: Shake It!, which took him back to his routes in a nice way. WarioWare released the extremely neat D.I.Y., and the different, but slightly disappointing, Game & Wario. With the WarioWare brand seemingly slowing down a bit, might we see a focus on the classic Wario once more?
* Fire Emblem: Fire Emblem Awakening was a pretty great game and, from my observations, really helped push Fire Emblem's popularity in the West and sort of move it towards a more mainstream series as opposed to being as niche as it was during the Melee-Brawl era. We may, or may not, have a Fire Emblem x SMT crossover coming out too, which no doubt will be pretty cool if it's ever actually released.
* Pikmin: Pikmin 3 was finally released, and it was pretty great! There's also an Anime Series in the works according to Miyamoto, but who knows if that will actually materialize anytime soon, and if it will be worth watching.
So-So's
* Metal Gear: Snake might not even be in Smash 4, and I'm not took up-to-date on Metal Gear Solid, but from what I've observed, you have people excited about the new MGS, and others who think the series jumped the shark with 4 and should just die. So, yeah, "So-So".
* Sonic: Well, he certainly improved a lot from 2006, with Unleashed, Colors, and Generations all moving towards a more solid series, but then Lost World sort of bombed and, well, it doesn't seem like Sega has yet to recapture the magic. He's got a "big new game" coming soon to all the next-gen consoles, and a television show, so, well, I'm willing to give him a chance. But if you ask me, what they really need to focus on is the next Sonic and Sega All-Stars Racing.
* The Legend of Zelda: Well, if you ask me, I found Link Between Worlds sort of underwhelming, a solid game, but nothing "mind-blowing". It was a bit too safe for my tastes despite the innovations with item obtainment, which sort of made things boring. Add in the fact only one big console game was released, Skyward Sword, which wasn't exactly the most well received game, and the lackluster Spirit Tracks, it certainly doesn't live up to the Melee-Brawl gap which saw Wind Waker and Twilight Princess. Oh, I guess Hyrule Warriors might come out before Smash 4 too, and, to be honest, I'm super hyped for that, but I don't think people consider a spin-off like that to be a sign of the series being the same status that it once held. I'd say Zelda herself is a "winner" though, for having a playable role in Spirit Tracks finally, and a really good rendition in Skyward Sword. Toon Link also wins since he wasn't cut despite claims he'd be, got featured in Spirit Tracks, AND his breakout game got an HD Release.
* Yoshi: On one hand, his own series sort of died out before Brawl, Yoshi Island DS basically putting the nail in the coffin, but on the other hand, we've seen a resurgence of him in mainline Mario starting with New Super Mario Brothers Wii and then going full force in Mario Galaxy 2. This year we may have two new Yoshi Series games coming out, however, one is looking to be very lackluster, and the other's basically disappeared from sight and may not even make it to release if things continue to go south for Nintendo. I think the fact he was the only Veteran left out of the Smash 4 reveal trailer basically says that Nintendo doesn't see him as a strong enough character on his own anymore.
* Earthbound: Still no word on an official English release of Mother 3, but, the translation patch was released a bit after Brawl, which is a good thing. And Earthbound finally made its way to the West via the Wii U Virtual Console, so it seems there's goodwill all around! Still, I don't think Earthbound is planned to be revived anytime soon outside of that, bar that one fan sequel in development, but who knows how that'll turn out.
* Game and Watch: Hard to call him a loser since, realistically, no one was really expecting a new Game and Watch Game. But he got featured in Nintendo Land, which is pretty good all things considered.
Losers
* Metroid: More so for the big fall in grace, as after 3 very solid games that revived the series in a new direction, and the Trilogy Collection being released right after Brawl, things went south due to one game: Other M. Not only was it a bad game functionally, but it completely soured people on the entire brand in a way that hasn't been seen since arguably Sonic 2006. Besides a spot in Nintendo Land as one of the bigger games, the future of Metroid is silent, and many people weren't too pleased when it was announced that Retro weren't planning on saving the series, instead going with Donkey Kong.
* Star Fox: He got a 3DS Remake of the N64 Classic. Well, it's better than nothing. Oh, and a bunch of "Platinum working on Star Fox!" rumors.
* Captain Falcon: Apart from the bare-bones GBA F-Zero featured as an Ambassador 3DS Game, he did get featured in his own game in Nintendo Land, although the fact it's called "Captain Falcon" and not "F-Zero" speaks volumes about the future of his home franchise. Will he become that dude known only for his crossover appearances?
* Ice Climbers: Outside of being featured in NES Remix, and Ice Climbers being re-released on the 3DS and Wii U, these two have yet to receive any big breaks outside of Smash Brothers.
* R.O.B.: Perhaps his inclusion in Smash Brothers Brawl may have been seen as a revival for him, yet he didn't return in any of the Mario Karts after being featured in Mario Kart DS, and none of his games were restructured for the Virtual Console (I'm not even sure how easy that'd be to do, though), and people still seem sore over his inclusion.