I, personally, am not to crazy about some of the new comers. I know that Ridley and King K. Rool were characters that a lot of people wanted, but I myself, never grew up with Metroid or Donkey Kong Country. It's still cool that they're in the game though. I personal would like to see a rhythm heaven representative, and see Bandana Waddle Dee in the game.
While I respect your opinion. Have you tried going back and playing some Metroid and DKC games? Everytime I see someone go "Cool for their fans but I don't know who they are/don't see the appeal" I always think "Wow they are missing out they should go back and play some of these games since these games are some of the best games of all time"
I'm gonna be honest here before Brawl released the only Nintendo franchises I played were Mario, DK,and Pokemon spin-offs. After I experienced Brawl I immediately went to see all the franchises I was missing. I've become a huge fan of all Nintendo franchises since. I bought every 1st party title on Wii and bought like over 50 VC games to catch up.
My first Zelda game was Twilight Princess. I LOVED it so much I bought Ocarina of Time, Majora's Mask, Zelda NES, Zelda 2, and ALTTP off the Wii VC. Also bought Link's Crossbow Training. Then bought Phantom Hourglass on DS. Played all of them and I enjoyed what I played of them (except Phantom Hourglass that game sucks). Haven't missed a Zelda release yet (except Skyward Sword and Spirit Tracks).
My first Metroid game was Metroid: Prime 3: Corruption. I LOVED it. Went and bought Super Metroid and Metroid on the Wii VC. Then bought Other M and Prime Trilogy when they released on Wii. Super excited for Prime 4 and eventually bought Fusion when it hit Wii U VC. Bought Metroid 2: Return of Samus on 3DS VC.
My first Star Fox game was actually Adventures I played it before Brawl came out over a friends house when I was younger didn't really care for it back then. But after Brawl I went and bought Star Fox 64 on the Wii VC. I LOVED it so much I went and bought a copy of Assault and played it on my Wii (really enjoyed it). Then I bought 64 3D on my 3DS and Command on Wii U VC as well as Zero. (Though I hated both Command and Zero) getting Starlink: Battle for Atlas day one though.
My first Fire Emblem game was Radiant Dawn on Wii. I remember really liking it but never finishing it because it was hard as hell. I bought Awakening on 3DS and loved it. I skipped over Fates and Echoes because I was over the 3DS by the time they came out but am really looking forward to Three Houses.
My first mainline Pokemon game was Diamond on DS. Needless to say I didn't really care for it (not an RPG guy) but I bought X and OmegaRuby on 3DS thinking "maybe I should give it another shot" needless to say they didn't grab me either. I'm gonna give Pokemon Let's Go a shot because I think the "casualness" of it (as well as it being on a home console) will bring me into the fray hopefully.
My first Warioware game was Smooth Moves and I adored that game. Bought D.I.Y when it came out enjoyed it as well. I also got Game & Wario on Wii U and thought the game was "meh" the only Wario game I played prior to Brawl was Wario World on GCN and thought it was okay. I also got Wario: Master of Disguise on DS in 2007 and that game is HORRIBLE! I bought Wario Land: Shake It on Wii and thought it was awesome. Which made me go buy the previous Wario Land games on Wii U/3DS VC.
My first Animal Crossing game was City Folk. While Brawl didn't have a Animal Crossing character I was always intrigued by the stage/trophies. I fell in love with it and the series. Bought New Leaf on 3DS and put HOURS into it. Super excited for Animal Crossing on Switch.
Now for my experience with Kirby...I played Air Ride a LOT as a kid but it was the only Kirby game I ever played before Brawl came out. I decided to go on the Wii VC and buy Kirby's Adventure, Dreamland 3, Kirby 64, and Kirby Superstar as well as Kirby Dream Course and Avalanche. Enjoyed them all except Dreamland 3 and Dream Course as well as Avalanche. So I bought Epic Yarn on Wii when it was released and it became my favorite Kirby game next to Adventure. Until I bought Triple Deluxe on 3DS which became my new favorite. I skipped over Return to Dreamland, Battle Royale, and Planet Robobot as both released on their systems after I stopped playing them. I bought Rainbow Curse on Wii U thought it was "okay" and bought Star Allies and also thought it was "okay kinda boring"
Then Kid Icarus. Bought the original on Wii VC. Thought it was fun but hard..didn't beat it. But I bought Uprising when it released on 3DS and loved it.
Bought Ice Climber too on Wii VC and thought the game was terrible. lol
Lastly I tried the Pikmin series after Brawl bought the New Play Control version of Pikmin when it released on Wii. I enjoyed it but it was stressful. lol With the time limit and micro managing and stuff. Then got Pikmin 3 when it released on Wii U and didn't put much time on it...just couldn't get into it but I'm glad I tried the series.
Wow this post became much longer than I expected basically what I'm saying is go back and try some of the franchises you missed you won't be disappointed. I've become a much bigger fan of Nintendo as a whole thanks to Smash Bros. Me as a gamer couldn't be happier that I opened my horizons a little bit more. I'm shocked at just how many people on this site haven't played a lot of Nintendo franchises/games actually.