A little off-topic but which Smash sequel has the strongest set of first three initial newcomers in your opinion?
Now that's a very interesting question indeed.
The nostalgic part of me says Brawl (partly because I wasn't aware of Melee's E3 2001 presentation when it happened - I was 10 at the time Melee's E3 presentation happened, and 11 when Melee released here in EU. I did catch Brawl's E3 2006 trailer though when it released), but upon reflection Melee wins.
* Peach and Bowser were obvious inclusions at the time - they were two of the biggest Nintendo could've gone for period. Ice Climbers was a giant ?, but Sakurai's initial design of them being a two-in-one-fighter helped their cause. Icies did become infamous for their chaingrabbing, but that was years down the road and within the competitive scene. Wobbles did lend his name to one of Icies' more infamous tricks - but he himself is a legitimately great IC player (reaching 2nd at EVO 2013). Bowser did struggle the first few games, but 4 and especially Ultimate finally allowed him to find his footing. Peach's been a consistent presence - the float mechanic has kept her unique, and competitive players like Armada have helped to keep her in the limelight. Strongest trio for me.
* Meta Knight and Pit opened Brawl strongly, and ZSS did show Sakurai's intent of letting Final Smashes have an effect on gameplay. The three (and Wario) did get overshadowed by "Snake? Snake?! SNAAAAAAAAAAAAAAAAAAAAAKE!" but otherwise, there were not many complaints. Although ZSS did inadvertedly sow the seeds of many angry Metroid fans and helped spark the Ridley fanbase (not helped by the fact that ZSS turned out to be high-tier in Brawl - higher than regular Samus - thanks to her dash attack chaining and mixups all over the place). Pit was mostly remembered for "HIYAYAYAYA!" (although Brawl did help Pit get Kid Icarus Uprising, so Brawl marked a positive turning point for him) but then... we have
. Mr. Peak Brawl. One of the most infamous Smash characters period, and arguably the character that settled the "whether tiers exist or not" debates; by confirming that he was so absurdly powerful (so many quick attacks) that he couldn't be ignored. Upon further reflection, third.
* Villager was, looking back, the kind of character one would expect to open up 4. AC has been a steady system seller by that point. Not the hypest reveal for me personally, but eh. Mega Man was, however, the big-attention getter at the time, and it showed. While WFT was mostly met by "Wuh - huh?" Perhaps the weakest trio overall from a purely "hype" standpoint, Still, a pretty good starting point. And although the trio did not get that much time in the competitive spotlight during 4's lifespan, they also didn't get the infamous reputation that later additions in 4 would get. While both Villager and WFT had infamous custom moveset combos that could slow games down to a crawl, that was more because Custom Moves was firmly in the "
Really neat idea, would've sorely needed more time in the oven and balancing." And 4's trio ranks... fourth, although it's not a bad trio by any stretch.
* And so, Ultimate. Inkling's, like Villager, the obvious get. Splatoon had done really well on the Wii U by the time selection took place, and 2 solidified that. It's only with the E3 2018 presentation that things reached a fever pitch. Not just "Everyone's Here!" - Daisy's inclusion and the new moniker "Echo Fighter" was a very smart move since it turned a dislike concept (clones) and made them much more palatable. Then, Ridley. To go back to ZSS' inclusion back in Brawl, that one had a major effect on Ridley's demand (and in the interim ZSS had become one of the more infamous Sm4sh characters due to her ladder combos). And Ridley's reveal was pretty much the moment when 12 years of built up frustration amongst some burst. It was at hype reveal for me personally, since Nintendo was going all in with the first parties.
* As for the trio's post-release fortunes... On one hand, Inkling's seen quite a lot of success at the competitive level, but the squid's seen some worsening fortunes the last year due to her weaknesses becoming a bit more apparent. Still, Inkling's rated highly overall. Daisy's reputation has soured since Nintendo chose to enforce her as a total clone (which soured people overall on Echoes, a lot of missed potential). Ridley's been in the background of the competitive scene due to his weaknesses being a tad too exploitable, although he still sees high-level play. Sill, second strongest for me personally.
What I'm meaning to say is: Reception at the time of respective release is different from now, especially from a competitive lens.