The Mane Six (any of them) getting colftriends is something I for one am 100% against, as we already have Cadence/Shining Armor for all of those lovey-dovey aspects the show may want to cover in the future (that was whole theme for 'A Canterlot Wedding').
The Cutie Mark Crusaders getting their Cutie Marks means no more wacky adventures trying to discover themselves.
'Princess Skyla' would feel redundant because we already have Pound Cake and Pumpkin Cake for take care of foals-like shennanigans for future babysitting episodes like we had with Pinkie in Season 2.,
Finally, Scootaloo flying.
I know that may sound cruel, but hear me out first;
I LOVE Scoots-in fact, she's my favorite Crusader.
And that's why I want her to remain flightless, but learning that her disability doesn't necessarily define who she as a lesson for the show's handicapped demographic-both young and old.
Plus, she was more or less already envisioned as such from the beginning and her weak buzzing and inability to hover more than a few seconds has all previously led me to believe that she is in fact, handicapped.
In that regard, I think it would be the most respectful thing they could do for the character, similar to Applebloom's realization in 'Call of the Cutie' after Silver Spoon and Diamond Tiara made fun of her for being a 'Blank Flank' and Scoots and Sweetie stand up to them and ask 'what's the problem with that?'.