I can't imagine a Smash Bros. without trophies, even if the first one didn't have them (sorta).
I have though a few complaints about what they did in Melee and Brawl.
In Melee, I basically hated all the alternative character trophies. We're talking about 54 (I think) trophies of playable characters with a different palette color which explained only the special moves. I agree on having more trophies for the same character, if it makes sense (like Mario, Dr. Mario, Paper Mario, Tanooki Mario... Not Mario and Mario 2 with Wario's clothes). Still it's true that they gave more attention on retro games which was nice.
Brawl had the good amount of trophies (which I hope is DOUBLED in Sm4sh, yes doubled) but the balance of distribution was terrible.
First, I didn't like 90% of the Subspace Emissary trophies. Aside from the fact that a lot of them were a real pain in the *** to collect, most of them sucked. Like that dude, the Arthionet, or the one who blows wind out of his mouth. We're talking about 50 trophies I think of original dudes nobody cares about.
Also, WAY TOO MANY pokémon trophies. I think it's the biggest category of all. Also, what's up with the caps lock? Why to we have "Pokémon Trainer" and "SQUIRTLE"? Never quite got that. I think there's every single starter ever, which is understandable, but it's better if they do trophies like "Generation II starters" with Totodile, Chikorita and Cyndaquil on the same stand next time, just to save two free slots. Also, their quality was really bad. I like when a trophy resembles the same kind of graphics the trophy had in the original game, but Pokémons just seem quite off and bland in Brawl. Something about the colors probably.
Kirby too had to many trophies if you ask me, especially when some other franchises like Mother, Fire Emblem and Metroid had so little. Why don't we have the Ultimate Chimera trophy? It even appears in New Pork City. Where is Mother Brain? It's like they don't want to show her because she's creepy as hell. Meh.
And finally, what happened to Sonic? Jet and Silver? Seriously? Blaze? What about giving the franchise some good trophies next time?
Something I would like for the next time:
- more trophies of stages or places in the franchise
- animated trophies, you tap A and the trophy makes a little animation, maybe even a sound
- just get rid of that mode in which you can put trophies and then make a picture of them, I think nobody really used that
- maybe they can make possible to switch trophies via online, pokémon-style.
- maybe something like a new trophy every day, how hard can it be? Like Level-5 does with Layton's puzzles.
About stickers, I kinda liked them. Sure they're cheap and all but some of them are good to look at. They're a pain in the *** to collect (I got to 697), so maybe a little easier next time, but they can stay.
Trophies are the priority though. C'mon they're relatively easy to make, just give me a whole bunch of them and I'm happy.