I keep seeing Grumpig and Sharpedo mentioned, yet I like to use those two quite a bit. Grumpig works if you're looking for a bit of a tank-ish Psychic type, while Sharpedo is a hard-hitting Water-type that is honestly much more interesting than a lot of the Water-types in other regions. At least to me. Funnily enough, my favorite Pokemon happen to be ones that not a lot of people like (my favorite of the weather trio is Groudon, easily the worst one competitively).