Well, well, well.
I was really impressed with your theorical justification... Until I saw the roster. And now I don't even know how to begin to express how flawed and mislead it is. Though (in bad English) I'll try to.
1st. All your essay is based in the idea that there won't be essential changes in the progression showed between sequels (although you contradict this statement by saying there won't be third-parties in the next installment). But have you taken a look at Smash geographical position lately? Nintendo, with WiiU, has recently sealed its condition of casual brand in the eyes of its fans. The first Wii could have been just a little blur in Nintendo's Golden Hardcore History, but now it's confirmed: the company has degenerated. By launching a SuperMario each year, like if it was some kind of CoD seedling, or stating that "Zelda will be targeting a broader audience" Nintendo is telling all of us what it has become. Even so, simultaneously, they hired Namco for the making of the next Smash and Sakurai said he would take balance more seriously, while assuring 4th would get more significant changes than the ones Brawl got. What I'm trying to say is that SuperSmashBrosU (and 3DS) is meant to be one of the last strongholds of Nintendo Hardcore Gaming. You could argue that Brawl was bestselling on Wii and that it wouldn't make sense to remove its casual-focused structure, but if you think in the incredible repercussion Melee had (and still has!) among the FGC you will easily see the strategical influence of bringing the franchise back to hardcore (besides, Smash nature lets casual-gamers have lots of fun even without tripping and the like). With this proofed change of direction, we must acknowledge the possibility of NEW RULES to the roster succession.
2nd. You overlook the great differences between roster successions, probably to make it easier to predict Newcomers thanks to a more solid pattern. I guess that's the reason because of which you praise every character choice Sakurai made (even R.O.B.'s!) as if they were objectively optimal. The most obvious gap is the one between real rosters and yours: while the first ones only included two "really fossil franchises" (Ice Climbers/Game and R.O.B./Pit) you anticipate two "really fossil franchises (Takamaru and Sheriff)", two "recently refloated fossil franchises (Palutena and Little Mac)" and two "lapsed characters (Dixie and Samurai)". The concept "recently refloated fossil franchise" is totally inedit in your roster, and the "rotten character" label has only been attributed to Sheik. But since Sheiks existence is a clear attempt to prevent Zeldas logical margination, it shouldn't be counted (though I would agree with Dixie if she ends coming with Diddy).
Progression differences between Original-Melee and Melee-Brawl:
- Original-Melee. Choice probably starts by picking the lacking main characters from the big franchises (Zelda/Sheik, Ganondorf, Bowser, Peach, Mewtwo and Pichu [one of the most emblematic second gen pokemon, for some reason]), then some charismatic fossils are added (Ice Climbers/Game) with a promoting saga (Marth). The rest is arbitrary cloning (Roy, Doc, Young Link and Falco). Were this choices as attractive, popular or representative* as Diddy or Wario? NO, just cheaper.
- Melee-Brawl. In the line of Brawl inputs, this one is too chaotic. DDD and Metaknight are not from a big franchise, but they have Sakurai's benefit for being his creations. Lucario, who is kind of popular, happens to be anatomically similar to Mewtwo, whose moveset casually needs to be recycled. Young Link is getting old. So does Sheik, but there's no WW replacement. Let's refresh Fire Emblem with Ike. Let's include Lucas, R.O.B., Wolf! Paper Mario isn't diverse enough! Bowser Jr. isn't that wellknown! Krystal has too many dedicated fappers! Golden Sun? Psynergy? What is that?
Franchise Proportions (you can easily see here how much interest is put in its balance):
- Mushroom Kingdom: 16% | 20% | 10%
- DK Islands: 8% | 3'5% | 5%
- Yoshi's Island: 8% | 3'5% | 2'5%
- Fire Emblem: 0% | 8% | 5%
- etc.
3rd. You are omitting the announced roster restraint. Sakurai stated it had "pretty much" reached its limit. Any prevision from then on should stablish a limit of Newcomers based on the exclusions that can be made. By the way, this is another reason to justify the direction change I predicted for the saga, since less characters enable more balanced tiers.
4th. As it's true that Sakurai isn't very keen on 3rd-parties, he doesn't have the last word. I can assure you Sonic and Snake were the bestselling newcomers from last generation. Even if he doesn't like to, he must regenerate the "guest" offer for new Smashs (it's an economical imperative). This way the franchise won't get too dirty, but at the same time each iteration is having its own identity, while honouring big sagas that can be ported to Nintendo.
*5th. Representativeness was mostly an omitted factor in Brawl because of the audience it was focused on, but we can clearly see how it influenced Melee's roster (being only 3 [Marth, Game and IC] the uncloned characters who didn't come from Pokemon, Mario or Zelda). If the 1st issue I commented before ends being true, the "representative orientation" of newcomers will come back from Melee. Of course, the representative influence of new characters from Mario, Pokemon and Zelda is quite limited right now (Impa, Bowser Jr, Toad and Waluigi are the only iterative ones that haven't been included until now [shy guy, koopa and the like aside]), so there's room for active inedit franchises like Animal Crossing, Golden Sun, Nintendo Wars (more or less), Paper Mario or even Sin & Punishment. Metroid, DK, Starfox and Fire Emblem may also deserve some refreshment (but adding two new characters for any of them would be crazy, since they are not that transcendent).
6th. Wolf over Krystal was insane. They appear in the same number of games (even if Wolf was born 5 years before), the only difference between them lies in their playability and transcendence in their games (and of course in their attractive).
Now, we don't need to destroy Brawl's roster to enable new characters entrance. If a Skin System similar to Wario's is included, more sacrifices will be unnecessary. Besides, Young Link, Pichu, Doc and Roy could come back without any problem. A Skin System would arrive by the hand of the customization improvements announced for the 3DS. It would be a panacea, a solution to make everyone happy.