let's play a fun game that can actually have a winner (in the next 7 years)
here's the third party percentage in each smash game
SSB64-0%
SSBM-0%
SSBB-5.13%
SSB4-3.48%
SSBU-20% (so far)
what doe everyone think the next smash games 3rd party percentage will be? this is the first time Nintendo went with "gaming all stars" instead of "Nintendo all stars" and even if some company's were difficult to work with in the beginning the sales of smash ultimate seems to have brought most companies on board to the point where smash get's special privilege's and discount's.
im going to say this trend continues and the next game will at launch have a...
SSB6-45%
percentage. of 3rd party's to first party's.
anyway goodnight! im barely awake so I think i'll just go to sleep now.
So first of all your maths are a bit off - Smash 4 has 5.88% before DLC and 10.34% after DLC, while Ultimate has 13.16% before DLC and 18.39% so far.
For the broader question, it is hard to say because bringing in so many guests is already unprecedented compared to other fighting games, which have only just got to the point where having 4 or 5 isn't considered unusual. Of course, that's because characters from other companies usually don't get pre-DLC slots (outside of Soul Calibur). Likely due to the contracts meaning that it's easier to give rights holders a cut of DLC sales than of the game itself.
Even with the level Ultimate is at, you're talking about a really large redefinition of what Smash is. The composition of the second pass definitely suggests that Nintendo still, for now, sees it as a Nintendo game with invitees first and foremost, not a company smorgasbord. The roster in and of itself is also freakishly large as it is, even without counting the various types of clone. Just for the sake of it, I thought I'd fiddle with some numbers to see how a 45% guest roster could even be achieved.
If the last two characters in Ultimate are third-party (which gets us to 20%) and there's no cuts at all, I'm pretty sure that this would require SSB6 to launch with 40 new guests and no Nintendo additions for a 58/129 = 45% ratio. That's more than twice the number of pre-DLC newcomers in any game in the series before you even consider the licensing costs - companies are not giving their IP away for free. There's only so many Jeannes and Shadows you can throw in to pad out the numbers; even if the Switch's successor launches in 2026, such a monster game is likely only halfway through development by then and would require some out of this world sales to make back its budget. That's not completely impossible to imagine, but, well...
So let's put cuts on the table. At the most extreme end, every series is pared back to a single character. In terms of current franchises, that's 13/38 = 34% guests. From there you only need to add 8 guest franchises to get to 21/46 = 46%. There's probably room to represent a few more Nintendo faces, which would require something like a 25/55 = 45% split to balance it out. But now people are in an absolute uproar because you've chucked out a lot of diversity and fan favourites to get to this point.
Finally, I'll look at a middle ground where there's some heavy cuts but they're less severe. From the current pantheon, if we keep
then you're starting out at 15/56 = 27% third-party representation. For newcomers, some viable adds are
First-party: Captain Toad, Impa, Cinderace, Tom Nook, Octoling, Ayumi, Isaac, and two peeps from late in the Switch's life that we haven't even heard of yet
Third-party: Raiden, Tails, Dr. Eggman, Zero, Chun-Li, Alucard, Lloyd, Heihachi, Crash, Coco, Doomguy, Layton, Hayabusa
This is already pushing past the limits of feasibility, particularly with minimal clones, and I can still only get the ratio up to 28/78 = 36%. That's the most I could see happening, and it would require the longest initial development period the series has ever seen. As I've said, a 45% starting roster really reshapes what Smash is and is hard to conceive of. I expect that whatever form Smash 6 ends up taking, the base roster will have 10 guests at most with the rest appearing as DLC.