I like that you get access to a Flying Pokemon so early on in the game. In this case, dual-typing is pretty useful. According to the Pokemon Wikia, Rowlet has access to a new Grass-type move called Leafage.
While we don't know much yet about Rowlet or his evolved forms, I like the overall design. It may not be my first pick among the three Alola region starters, but I'll be happy to give him a chance at a later date.