The Kirby series is not misrepresented, it has all the basic main characters in the roster and all; but so far, it's like if Mario only had Mario, Luigi and Bowser.
The series has evolved and went through many different cycles.
I think a big part of the Kirby series is still not represented and that's unfair.
What I would add/change?
I would add 2 characters, for a total of 5.
-1 character from the games directed by Shinichi Shimomura (Dream Land 2, 3 and 64)
-1 character from the modern series (All what comes from after the soft reboot of Nightmare in Dreamland, especially since the Wii game).
Also, I would like to represent some recurring categories of characters that are still missing from representation:
-Friendly character (not a villain turned good), Humanoid/fairy-like, magical artist
-Final boss with creepy final form, betrayer, mage/wizard
The two characters are obviously Adeleine & Ribbon, and Magolor.
I'm not a big fan of Magolor, but I think that he would be the best character to represent the modern Kirby games, as he's the most iconic of the bunch.
Some bonus stuff that could be added to improve representation are the Animal Friends (Rick, Kine and Coo) as assist trophies and Galacta Knight as a Metaknight echo.
final roster:
-Kirby
-King Dedede
-Metaknight
-Adeleine & Ribbon
-Magolor
echoes:
-Galacta Knight
The Zelda series instead needs some more work.
Lets start with the characters who I think should be kept as they are:
-Link
-Zelda
-Ganondorf
Let's say, forget about everything else for now.
About Link:
We have many different versions of Link, but I think that all what we need is just 1 Link. Not even Toon Link... What's the point of having another version of the same character if all what it represent is just a different art style? Then we should have Classic Sonic, Classic Pit, 8-bit Mario, etc.
I think they should get enough self confidence and scrap the Link clones, they are unneeded.
If anything, you can keep Young Link, as long as you give him an original moveset based on the ocarina and the masks... but even that is a bit too much fanservice and not really needed. But you know what? Young Link with masks can represent three of the most iconic races from the Zelda series, Deku, Goron and Zoras, so, I'm not sure.
Zelda:
Zelda is fine... yeah. If they want to keep this regular/toon distinction, then I think they should also add Tetra to represent the "toon" version of her, but as I said, I think that separating regular and toon as different characters is as much unneeded as having Doctor Mario along with Mario as a separate character.
Well, at least Tetra would get an original moveset... but it's a low priority IMO.
Ganondorf:
Aside of changing his moveser a bit to match his source material more, Ganondorf is fine as he is.
But Ganondorf is not enough. I think he is ok, but limiting Ganon to just a final smash is a waste of potential.
Ganon has a specific classic design that's very iconic and has been recurring in a lot of games.
So, I would keep Ganondorf and add Ganon too as a separate character.
now let's add some characters:
Impa:
It's Sheik. Sheik is not relevant anymore, Impa it's a better character to represent the sheikah. Aside of the name and appearance change, she can keep the same gameplay as Sheik for what I care.
Ganon:
The blue pig with a golden trident. Based on his classic design, this character would represent the classic games in the series, from the very first game to A Link to the Past, including all those remakes/sequels made in more recent times that are still based on ALttP design-wise (4 sword adventure, A Link Between Worlds).
Tingle:
Come on.
You know, he's ugly, he's a joke character, and all, but all things considered... he has been an important character in the series for many years, he has got some spin-offs where he was the protagonist (most of them were Japan exclusives though), and uhm... well... yeah, he's that type of character that Smash needs, those characters who you shouldn't take seriously, those character who are there for the WTF factor and for being funny.
Wii Fit Trainer and Piranha Plant to name a few.
That's it
final roster:
-Link
-Zelda
-Ganondorf
-Impa
-Ganon
-Tingle
Mario (not counting the Yoshi, Donkey Kong and Wario sub-series):
1: Toad.
For many years I agreed with Sakurai's choice of not including Toad, because, while he's an important recurring character, he never had anything special to add; he most of the times just jumps and runs, or does exactly what Mario does (probably the same reason why Slippy and Peppy are not in after all those years despite being main characters).
Not even Captain Toad in Super Mario Galaxy changed my mind...
But then, Captain Toad: Treasure Tracker happend.
Now Toad is not much different than Yoshi: he has a spin-off series, with a specific gameplay associated to him. I think that because of this, he now has no reason to be absent from the roster.
He should definitely be in, but not as Captain Toad... I think he should be in as Toad, just Toad (the captain can be a costume).
Not just that, but Toadette has got some spotight as well and she can work very well as a Toad alt.
Toad can even stay in Peach's moveset, and at the same time be his own character in a separate slot; there is no problem with that as there are multiple toads in Mario's universe, and there are cases of the same character appearing multiple times in separate character slots (Samus/Zero Suit Samus).
2: Doctor Mario can be a costume, there is absolutely NO need to have him in the roster.
3: For some reason I think that Bowser Jr is a weak choice as a character... I think that he is a bit too much "secondary" as a character, kinda the same as what I think of Sheik. Well, Bowser Jr appeared in many more games and there is also Baby Bowser who's technically a different character, but they are very similar and it works well to represent him as well. Also, he adds some original gameplay involving the Clown Car... and he includes the Koopalings.
Though, I think that Bowser already represents the Koopa species well enough, and IMO Bowser Jr is not really needed. His gameplay, while original, is also a bit generic: it doesn't represent iconic game mechanics/game elements nor the character is iconic himself (unlike Rosalina). The two good things it does (representing the clown car and hammers) could simply be added to Bowser himself by updating his moveset. So, I'm all for combining the two movesets into one and improving Bowser instead, while removing Bowser Jr. But this is not much important, I'm also fine with just having more characters.
4: I would change Luigi to be even more different from Mario, and to be based even more on Luigi's Mansion. Well, to be honest, I would even remove him from the Mario series and consider him as part of his own series, along with E. Gadd as a newcomer sometime in the future.
5: I would remove the F.L.U.D.D. from Mario, and eventually transform it into an item that everyone can use... that and make it so that it cleans Inkling's ink.
Or, even better, give it to E. Gadd along with Bowser Jr's paintbrush and other gimmicks, and build a moveset around that.
final roster:
-Mario
-Peach
-Toad
-Bowser
-Rosalina & Luma
-Piranha Plant
echoes:
-Daisy
new sub-series - Luigi's Mansion:
-Luigi
-E. Gadd
In total, that's 6 newcomers, 1 new echo, and some veteran movesets revamped... it's quite a lot of work for just 3 series (even though they are important series) but I'd rather have this than more unnecessary gimmicks such as the custom moves in Smash 4.
There is more about other series, but I think the post is already long enough.
: Needs more Kongs, and one other non-jungle stage. Ultimate did pretty well in fixing the previous glaring issues, though it has a long way to go.
