If you thought Saga Creatures were complicated in and of themselves, wait until you see the flip Creature/Saga Creature cards Final Fantasy has to offer
Getting 9 power for 4 mana in a game with 3 opponents is nothing to sneeze at
If a Vehicle has a wild, super-fun effect on it, then all that tapping of creatures is worth it, but once we are outside of Standard, Vehicles are worse than just playing creatures
Red often requires you to discard as part of the bargain, sometimes giving you card "selection" but not actually card "advantage." Black is the most likely to cost you life and White is just the worst, often having to rely on shutting down an opponent's extra draw in order to get your precious extra cards
On the flip side, however, this archetype is well-suited to dominate grindy games