Soltari Visionary has been the favorite at this level, since it combines a creature with enchantment removal, but the cheaper Monk Realist is probably a better choice for that role now. Vec is a White Knight that's unblockable and practically unkillable by almost half of the typical tournament decks. Unfortunately, the increasing popularity of green makes the Paladin less effective. Knight of Dawn may be a better choice in the current metagame. Enhancers and Equalizers N ext come spells to make the weenies bigger.
Crusade is the traditional choice.
It pumps all your white creatures and requires an anti-enchantment spell to remove, so it's difficult for black and red to destroy. If you're playing Extended format, Empyrial Armor trumps Crusade. Although it can be negated by a blocker with regeneration or protection from white, it forces your opponent to deal with it immediately or lose fast-as early as turn four. In the old days these decks almost always used Armageddon or Winter Orb. Cataclysm became a favorite combo with Empyrial Armor, but Cataclysm is less attractive now that Armor has rotated out of the Standard environment.