Re: Commonly used Pokemon and their benefical natures
I think Feebas is good Modest, but for a more defensive moveset, you'd go with Bold. Flygon is better with a Jolly nature because with proper EVs, he'd still get good attack. Geodude is much better Impish. It has good defensive abilities and hardly ever uses his special attack. Adamant could work depending on what you give him.
And I'm going to have to disagree with an Adamant Umbreon, Careful is way better considering he has terrible attack stats and he used for Tanking, not attacking...
Leafeon should not be Modest, ever, sp.atk is his worst stat. Jolly is the best he can get with Adamant as the second best.