The Dracanomicon has one dragon stated for each MM type and age category.
otherwise you have to choose them for each dragon.
There are standbys from PHB and MM that no dragon should be w/o
Power attack
Improve Initiative
Multi-attack
Hover
While the Draconomicon has lots of great dragon feats:
recover breath
awaken spell resistance
clinging breath
shape breath
rapid strike
improved flyby attack
overcome weakness
Quicken breath
Other Sources / borderline feats
Practiced spell caster
Obtain familiar - "why yes the cat seems to have more than 100 hp, maybe its killed a lot of commoners"
Wild Psionist, Psionic strike, deep strike, Psionic meditation
Armor Prof. - barding is a cheap way to get +4 or more AC, you just have to have servants.
Ability Focus
Expertise
Improved Critical
Weapon Focus