Someone here posted a pic of the beginning of the game where Alisae and Alhpie were sitting in the carriage on the way to the main city and pointed out the fact that Alisae had red pants and later became a RDM. Alphie wore blue...possibly symbolizing him becoming a blue mage. Could be reaching...but FFX-2 had a version of the Blue Mage called a gun mage. They also had a special skill called fiend hunter which could be a play on "ShadowHunter."

And we all know how SE loves to tease the next class in the MSQ...Alisae/RDM, Thancred/NIN