1 Mario - Basic all rounder that has something for everything. No loyalty to the character at all though, and unsure if he's too slow or too basic.
3 Link -
Smash 4 Link helped me realize the importance of short hops along with being the only character with 90% fast fall speed making me fast fall more often. Smash Ultimate him and Joker are the only ones with 90% fast fall speed that I know of. Also his bombs allow for zair drop combos which can be pretty input intensive. He also has reasons to use b-reversing as well. Main problems for him is that it can be easy to rely on projectiles to not do the input intensive actions.
Young Link is also a consideration bececause he is more consistently speeding up everything else, but at the cost of no zair drop combos which can be good or bad.
7 Fox - Simplistic, but can be complex, making it easy to stick with him and improve over time. Was the original character I was going to main, so would make a great 20th anniversary main. Also would make transitioning in Melee easier if I were play that game again. However, I have no loyalty to him outside of smash and I like Wolf more in general.
8 Pikachu + 19 Pichu - Fast and heavy reliance on combos. Along with emphasis on being aware of how high/low opponent attacks go since they are small. The only big thing against them is that quick attack can just nullify some of the unique advantages that some characters have, and it's almost a free recovery. I'm more biased towards Pichu because I love a good underdog character, and I love glass cannons. Also the self harm mechanic makes me choose my moves and when I attack more carefully.
11 Captain Falcon - He seems to be a pretty solid character for getting better with inputs and reading the opponent. I've always viewed him as the face of Smash, so what better character to improve with than that? Only real downsides is that he doesn't really seem to have any mixup options for recovery..... Also sometimes I might be tempted to play casually because it's just so fun to punish low to mid level players by spamming falcon punch and seeing how much I can get away with that.
15 Ice Climbers - I want to get better at speeding up my fingers for inputs. Controlling two characters would probably be very good for that. Also gets me used to looking at multiple places on the screen. Ice Climbers look friggin awesome when they played well too. With that said, Ice Climbers might be a bit too unique for some of the stuff I pick up with them to go to other characters. Also, while I maybe the only person in my town to have played Ice Climber on the NES, I don't have loyalty to the characters outside of smash which can be a problem to stay with them.
16 Sheik - When I look at all the characters in the roster, Sheik is the character I look at and see being rewarded for good inputs the most. There's a few characters that come close though. Only problem with Sheik is I don't know if they'll return for Smash 6, and if I don't improve enough with Sheik, I'll blame myself more harshly compared to other characters, which may make me more likely to quit smash competitively. However double edged sword, if I improve with Sheik fast enough, I'll probably feel better about myself and be more likely to be diehard about loving smash competitively.
20 Falco - Similar to Fox. However I don't know him all that well compared to the other spacies, so I don't know how well he could help with inputs. He just keeps changing every game.
21 Marth + 25 Roy - Marth was my Melee main, which is probably why my spacing is so good with many characters since the tipper is so important. I could go back to him and master the other things about him that my newbie Melee self could not even perform. However I'm tempted to play Roy because he is just more interesting to me due to him being faster, and seeming more combo focused which could lead to more input practice. Also Roy could teach me how to be a bit more aggressive when I'm unsure about what to do, since a lot of the time I'll back off when I don't know, which can make me predictable.
28 Dark Pit (and maybe Pit too) - First character I've gotten into Elite Smash. Seems to have a bit of everything. Only problem is that they are a bit slow. However that would just be a bigger emphasis on proper inputs.
29 Zero Suit Samus - I tend to like to watch the opponent's movements when I don't know what to do at all, ZSS is one of the characters that allows me to do that, but she also is fast and has an emphasis on combos, and uses b-reverses quite a bit. Only worried she might be too good and not seen enough leading to some easy wins, making it harder to want to improve.
38 Sonic - Similar to ZSS in a lot of ways, and b-reversing usage is a bit more specific. However it'll be easier to stick with Sonic since if there's any 3rd party that will stay, it's gotta be him. Lots of nostalgia with the character so it'll be easy to want to play him over some others.
41 Lucario - Going to be chilling in VRChat as a Lucario while I record myself training, perhaps talking with friends while I play. Would be appropriate if I was playing Lucario. Also Lucario shows a huge difference in speed when you add short hops and b-reverses, which are things most characters in the roster can use. Since there's a huge difference, there's a big reason to continue doing those things compared to most characters. Got some special nostalgia for him that will always give me a reason to main him. However since he is slow normally, I wonder if I need a faster character to improve more.
44 Wolf - My favorite of the spacies. Simple to start, but hard to master like Fox. However I worry he might be a bit too simple to do well with, making it hard to not try to improve.
50 Greninja - Feels like the speed of Sheik, however it feel like you can't just throw things out and you'll hit the opponent like Sheik. It feels like everything has to be planned ahead of time to hit people with Greninja. So while he may not press as many buttons as Sheik, he feels a lot more deliberate while still being quite fast. Only problem is that I have no character loyalty for them at all, making it more difficult to stay with them.
51 Mii Brawler - I'll be honest I don't know enough about the Miis since I don't usually see people play them seriously. Brawler seems to be quite fast and has a few combos though. So there is some potential. No loyalty to the character, but ya know, if I had a character to dress them up as, I might be able to. All the miis have really friggin fun gameplay though.
60 Ryu + Ken - Practicing inputs? Ryu and Ken have a lot of those, and would help transition me to Street Fighter if I ever get into that game. However, they have a unique problem where they have heavy+light attacks, so c-stick usage only seems to ever do one type. Getting used to doing tilts normally may limit what I can do with the rest of the roster when I would use c-stick for other characters.
64 Inkling - Another speedy combo character that is fun to play with. A bit of nostalgia along with being in a discord primarily for Splatoon, but also some of the best and most frequent smashers I've played with. Main concern being their recovery is rather free, and I hear that inkling may rely on bair a bit too much.... Also roller is probably too easy to streamroll lower level players with.
71 Joker - If I was designing a character for smash for my first time, Joker is very close to what I would've come up with.... Except Joker is stronger, and he also has the Arsene mechanic as well which is pretty ridiculous, and I thought 90% fast fall speed was supposed to be unique to Link. Also Joker looks really cool, and would be easy to main despite never playing Persona. Based on my time I've spent with Joker so far, my biggest fear is that Joker is a bit too easy to do very well with.
74 Terry - Ryu/Ken but easy mode. Still heavy emphasis on inputs, but just not as insane. If I'm having a bad day I can still do well. However, better inputs make him better so it works out.