Oh my goodness, I am so hyped for it! Smash is my favourite game series period, and I can't wait to see what they'll do!
First of I'm expecting the game's physics to be very similair to Super Smash Bros. for Nintendo 3DS and Wii U. The graphical style of the Inkling's model clearly shows the game will be similair to the previous games and it's almost an accepted fact that it's based on the groundwork laid by 3DS and Wii U. I have read some people speculating the game will be a little slower than 3DS/Wii U to accomodate for the smaller single Joy-Con controllers, and I don't deem that to be out of the ordinary, but I hope they keep the physics as close to 3DS and Wii U as they can, because I think they perfected it in those titles.
I'm also wondering whether 8-player Smash will return. I don't doubt the Switch can handle it. However, my main worry is the Switch's handheld mode. 8-player Smash can already make characters hard to see on a TV in the Wii U version, so in handheld it would probably be unplayable. I wouldn't be surprised if they either cut the mode entirely or disable it in handheld mode. But these are just guesses.
Characters
As for characters, I have to admit, Most of my wishes have been granted in Smash 4. My two biggest wishes were Miis and Bayonetta, and I got them both. So I don't have any huge wishes. Below are my personal wishes, in order of likeliness.
Bandana Dee (Kirby)
The Kirby series is a series that will never lose it's trademark charm. It's also a very succesfull series and one of the most important Nintendo milestones, and it totally deserves a fourth rep in Smash. And Bandana Dee is the most obvious option. We all know the arguments already: He's basically the fourth main character after Kirby, King Dedede and Meta Knight. He has obvious potential for a unique and cool moveset. I've really grown to love the idea of Bandana Dee making the cut, so he's got my support.
Spring Man (ARMS)
ARMS has been a success on Switch, it would be an obvious choice to give this new franchise some representation in Smash. I mainly want him in for his moveset potential. Having extendable arms could make for a really fun and unique moveset, as a long-range character with noticeable lag on his moves. I think Spring Man could be a very interesting addition to the cast.
Decidueye (Pokémon)
A new Pokémon is a given. Many people have rooted for Decidueye, and I'm right there with them. We need some grass-type representation in Smash now that Ivysaur is gone, Decidueye has a lot of potential as a ranged projectile-based character (like a faster but weaker Zelda with more physical projectiles) and he's one of the most beloved and recognisable Pokémon now. Keeping in mind likeliness as well, I think Decidueye would be the perfect candidate.
Waluigi (Super Mario spin-offs)
Even if I'm not the biggest Waluigi fan myself, I will admit I'd like some representation for the Mario side series. And when it comes to the side series, Waluigi is a staple. I have to give a shout-out to Daisy as well, who would really be my choice since she's my favourite Mario character (fight me), but Waluigi is more likely and, in my opinion, well worth giving a spot.
Assist Trophies
I personally like speculating about Assist Trophies as well. Assist Trophies are the way of giving characters and series representation without making them characters. There are tons of characters/series I'd like to see represented in Smash in some form, and Assist Trophies are the best way to do it. So, without further ado, in order of likeliness, my wishes for Assist Trophies.
Wonder Red (The Wonderful 101)
The Wonderful 101 was an underrated gem on the Wii U. Considering the good relationship between Nintendo and PlatinumGames giving the series representation in the form of an Assist Trophy isn't too out of the ordinary. Wonder-Red would first appear, and he would proceed to attack the fighters with various Unite Morphs (most notably Unite Hand, obviously). It would be a simple Assist Trophy that hops around the screen to deliver quick attacks with high damage but low knockback, similairly to how the combat in the original game feels.
Pauline and Mini Marios (Super Mario spin-offs)
When Pauline appeared in Super Mario Odyssey I was overjoyed. I had been wanting to see her get the representation she deserves for ages, and I think she more than deserves to keep that up in Smash. Her most prominent appearances before Odyssey were in the Mario vs Donkey Kong series, so I think she could use the Mini Marios to form a really cool combined Assist Trophy. She would appear in her red dress, and proceed to wind up a bunch of Mini Marios. These would then walk to the left or right in a straight line, falling off platforms and turning around when they bump into a fighter. They are rather weak, but some can wield hammers which will cause heavy knockback.
Jeanne (Bayonetta)
I fully admit it. I'm a HUGE sucker for the Bayonetta series. It's my second favourite series of all time, and I would love any representation at all. And with Bayonetta 3 on the horizon, I don't think an Assist Trophy is too out of the question. After all, all non-DLC third-party characters always got an Assist Trophy, and Bayonetta would fall under that in the next title. And with Jeanne being the most popular Bayonetta character after Bayonetta herself, I think she's ripe for the spot. Her moves would be inspired by her fights in the original game, where she would alternate between firing very powerful rapid-firing bullets and summoning various Wicked Weaves ranging from regular punches and kicks to more extreme Infernal Demons.
Style Boutique Girl (Style Boutique)
...So let me explain. The Style Boutique series of games has been a smashing success on DS and 3DS, which has gone criminally unnoticed by the main Nintendo fanbase for how good the titles are (for what they want to do, of course). I like this series and, even if its unlikely, I would like some representation from it. With this Assist Trophy, a random girl from the series (or whichever is the most relevant in New Style Boutique 3) appears, and using the power of fashion she would change everyone's pallete!...Unlikely? Absolutely? Lame? Perhaps. But I would still love it.
Flipnote Studio Frog (Flipnote Studio)
Anyone who grew up with a DSi has insane amounts of nostalgia for Flipnote Studio. This quirky little program still makes me gush in nostalgia whenever I see an animation from it pop by. I think that the Flipnote Frog deserves one final appearance as an Assist Trophy in Smash. He would show up in his pixelated form and make his trademark "ribbit"-sound, before summoning one of the default Flipnotes that came with the original game. These include the Ninja, the parade, the cat on a skateboard, the hairy monster, and of course the buttkickers.
Pyoro (Pyoro)
As an alternative to Flipnote Studio Frog, you could have Pyoro. This quirky bird from the DSiWare game Pyoro (also known as Bird & Beans) already appears as a stage hazard on the Gamer stage, but if that stage doesn't return I think Pyoro could be an Assist Trophy. I just really want to represent the DSi and the DSiWare platform, and Pyoro could do this well too. If Pyoro appears, beans would fall from the sky. If they hit users they would damage them and knock them away a small bit. Pyoro would be walking around the bottom of the stage, lightly knocking away fighters that touch him (like Fletchling in Smash 4). However, Pyoro would sometimes stick out his long tongue to catch a berry from the sky. If this tongue hits a fighter it can either deal a decent amount of knockback on its own, or it can drag fighters down towards Pyoro, where he'll knock them away. Either one can work.
Reckless Wii Remote Guy (Wii)
Can you notice a pattern? Yeah, I really like these out-there characters that are simultaniously unpopular and well-known. I'm sure many of you know the meme that went around during the ballot where people wanted Reckless Wii Remote guy in the game as a fighter. While that's obviously out of the question, I think putting this character that appeared in every single Wii game in as an Assist Trophy could be hilarious and a nice nod to the Wii-era. He would simply flail his arms around knocking away anyone he hit (but he'd wear his wrist strap!)
Tetriminos (Tetris)
I put these at the bottom because it's no secret there's still some conflict regarding the ownership of Tetris. Hell, the most recent example of this conflict was Tetris being pulled from the 3DS Virtual Console. However, I still think this would be an awesome Assist Trophy. Tetris was one of the biggest contributors to the Game Boy's success, and it's one of the most recognisable games out there, and in my opinion it more than deserves a spot as an Assist Trophy. The Tetriminos would obviously just fall from the sky, knocking away users they hit.
So, yeah. To summarize I'm super excited for the next Smash. I know most of these predictions have a 0% chance of happening, but hey, that's what dreams are for, right? :p
Can't wait to see who will actually make it! And you can bet that when it comes out I'm playing the hell out of it!