The implications of Twilight Sparkle becoming an alicorn

One subject that has interested me in recent times is of the potential implications in the fourth season and beyond of Twilight becoming an alicorn. By now it's of course no secret that Twilight has gained wings and a potential new role in the story, but there is still much to be extrapolated about it. Will Twilight assume a new role in the show's course?- Will she be replaced?- Will the show itself take a new turn out of slice-of-life to accommodate Twilight's alicornhood? There are reasons to debate all of the above, as it is an issue which greatly concerns the future of the MLP fandom.

I. WILL TWILIGHT ASSUME A NEW ROLE IN THE SHOW?
This is, I believe, the question with the least satisfactory and certain answer.

There are three major possibilities for Twilight: either she remain an alicorn and become a supporting member of the cast much like Celestia is right now; she remains an alicorn and rejoins the main characters to assume the same role she had previously; or she reverts back to being a unicorn and reassumes the role she had previously. Out of these three major possibilities, we can easily discount the last as being a particularly likely option, as Hasbro has naturally been pushing the notion of "Princess Twilight Sparkle" fairly hard in promotional material, and the meaning of fulfilling destiny (as notoriously stated in the Hasbro's season 3 promo commercial) usually implies a sort of permanence. Given that they forced this change in to begin with, nothing short of a major decrease in Twilight toy sales would convince them otherwise.

The other two options both have at least some evidence pointing to them. The idea of Twilight becoming an alicorn and assuming a role as a supporting character on the same level as Celestia is right now would not clash too heavily with canon, and it would not be out-of-character for her to assume duties at Canterlot and tutelage under Celestia as long as she had the opportunity to visit her friends on a regular basis. Given that Celestia pops up fairly regularly in snippets or portions of various episodes, it would not be difficult to end up writing Twilight into much the same role - possibly even replacing Celestia as the "friendship tutor" of the main characters and relegating Celestia to the same role Luna now occupies.

The idea of Twilight becoming an alicorn and rejoining the main cast may be a bit harder on the writers, but would still ultimately be possible. If either of the two would be considered a "lesser" possibility, this would probably be it: there were an abnormal amount of episodes in Season 3 which Twilight played no part in whatsoever, and all three other alicorns in-canon have been revered on much the same level as saints, which may make scriptwriting for the episodes awkward and clumsy as the writers try to justify how to avoid a running gag of "Everyone Twilight meets immediately bows down to her." There is also the issue that the moral of friendship may be harder to justify in this scenario, as Twilight now essentially occupies a position of absolute or near-absolute authority over all her friends. However, all of these clashes with canon could easily be disregarded if it would benefit toy sales and the continued success of the show. If this was done, I would foresee clunky and awkward episode writing, oftentimes slightly overlooking established canon, until the writers learned how to roll with it. There is one other major problem with this, which leads onto the next point...

II. WILL TWILIGHT BE REPLACED?
So far, the main cast has been meticulously tweaked to maintain a balance of diversity of personality, color balance, and species. There have been two unicorns, two pegasi, and two earth ponies; there have been ponies with the major color schemes of purple, white, blue, yellow, orange, and pink; and the only remote overlap between personalities has been with Applejack and Rainbow Dash, who nonetheless are immediately distinguishable from each other by their actions alone.

But Twilight graduating to alicornhood throws all of this off. Now the diversity, which was previously so well-formulated that it could not have been accidental, has been thrown off, because there are now two earth ponies, two pegasi, and... a unicorn plus an alicorn.

Why is this a concern? It comes down to, yet again, toy sales. The addition of a seventh main cast member, more specifically another unicorn, would provide more opportunities for Hasbro to make money via increased toy sales and would result in the balance being restored., even if there would be some canonical issues with introducing a main cast member that is not an Element of Harmony (and even then, the statuses of the Elements after the recent finale are uncertain: it could be very likely that Twilight now controls all the Elements).

The most immediately recognizable existing candidate for this role is, of course, Trixie. She's been in the toyline before, she's been in the show before, and has assumed a fairly major role in the MLP fanbase as a popular and well-known unicorn. However, several things establish her as a poor replacement for Twilight: for one, she is blue, which would not restore the color balance. And even then, she's too similar to Rainbow Dash in terms of temperament: Trixie is prideful, oftentimes lapses into arrogance, is ambitious, is an example of the age-old jerk with a heart of gold... There are too many similarities between her and Rainbow Dash to end up justifying her possible position in the main cast, and to me it remains a remote possibility.

A good picture can be constructed of the "ideal" candidate to the main cast: the pony would be a unicorn. The pony would have a vibrant color scheme predominated by either red or green. And the pony's personality would not be similar to the mane cast members. Naturally there are far too many personality traits to make a reasonable prediction on this, but some guesses could be made. What about a unicorn who is relatively laid-back, calm, thoughtful, and ? What about a unicorn who is given to being quiet, reserved, and averse to outward showings of emotion? What about an artsy unicorn with acute taste in music and a liking for more "contemporary" and meaningful experiences?

Amusingly enough, as the last example shows, of all ponies Lyra is now a potential fit to be amended to the main cast. Whichever character or archetype is chosen, expect there to be a massive and odd increase in the amount of importance Hasbro gives to a red or green unicorn in their toy lines months in advance, if this prediction is true.

III. WILL THE SHOW MOVE AWAY FROM ITS SLICE-OF-LIFE PLOTLINE?
This is more of a theoretical question, but still remains possible. So far MLP has been primarily focused on the everyday activities of the main characters, and while sitcoms have proven for decades that it is possible to indefinitely sustain a slice-of-life show with ease, MLP is almost perfectly set up to be a more adventure-oriented show, at the potential expense of it losing a bit of its emphasis on the nature of friendship.

This would interestingly line up directly with Lauren Faust's vision of MLP: as a show that may be "girly" in nature but not in content. The nature of the setting means that there are a plethora of various places to visit which could promise a very large amount of toy ideas for Hasbro; a recurring villain could easily be introduced and sustained; and the show wouldn't even need to lose its emphasis on friendship, as episodes could simply highlight an issue, disagreement, or more positive event that happens within the main cast, with Twilight continuing to send letters to Celestia about friendship.

Is there any reason that this needs to happen because of Twilight's transformation? No - the show is just fine without the adventure-oriented plotline, but given that the show is already shifting away from the status quo via Twilight's alicornhood, it is far more likely than at any other point that other changes will come, and earlier iterations of MLP have also delved into more adventure-oriented content, showing that Hasbro would consider such things if it meant increased toy sales. There are of course some issues with this idea - potential decreased sales of Ponyville residents such as the Cutie Mark Crusaders, Zecora, the background ponies, etc. - but all of the aforementioned characters could easily be written in anyways.

IV: CONCLUSION AND ADDITIONAL THOUGHTS
Even if Twilight is now an alicorn, that is no reason to lament the decline and demise of the franchise. The writing team of MLP has already shown beforehand that they can avert disaster by redeeming Shining Armor and Princess Cadence as likable, welcomed members of the supporting cast despite their dubious natures and origins; it would in all honesty be far more unreasonable for them to sputter out and die when faced with another scenario that they have had plenty of time to prepare and think for.

Yes, the famous "alicorn leak" from Reddit indicated that the writing team was unsure of what to do after having the Twilight-as-alicorn change foisted onto them to produce toy sales. But it's also been quite a few months since then, and given that the writing team must have been good enough for MLP to become popular to begin with, it becomes extremely unlikely that a team of a good dozen or more extremely talented writers had a collective brain fart and could think of nothing to save the franchise from being ruined forever by this choice from Hasbro.

My stance on the matter has remained much the same after the finale as it was before: wait and see. For now, I trust the writing team to not muck things up too badly.