What do you think would be one of the better advantages of being a water type?
I could list a number of reasons.Many of them are from Bulbapedia.
-Being a water type,you get the MOST amount of pokemon so that means a lot of diversity.What I mean is something like Quilfish won't be like Swampert or Empoleon or Alomomola.
-You have only 2 weaknesses and if you are a water/ground,you can handle both types quite easily.
-It is the type that gets paired up with the most types as in dual types except fire.This means even MORE diversity.
-There stats are even and not solely strong on one type or weak in another type.
-It beats three of the most threatining types:fire,ground,rock
-With many dual type pokemon with many different types,you get to get a big movepool on many pokemon.
So,that is why it is one of the better advantages of being a water type.