Don't forget though that for example Sea-Salt Ice Cream (or Ice cream in general when counting Birth by Sleep) just became such a big thing in the series was because Nomura tasted it while on a visit to Disneyland Tokyo and found it interesting enough to include.
So while it could be Disney's doing, it could also be just Nomura or someone else influential on the development team who took a liking to those attractions and proposed to include them.
And frankly, I rather see Sora gaining something new, possibly unique to him in the ability department rather than copying moves from other characters.
Terra may whip out a giant rocket launcher, Ventus six light blades in wing formation or Aqua taking flash step up to eleven, yet Sora now can whip out dual pistols like a male version of Lara Croft, sounds legit and lines up good with the rest of the wacky stuff.
And when Ansem can summon up a weird Zombie-organic airship or Xemnas his metal dragon, Sora riding a magical train doing some stuff does not seem to be too much out of place for the series.