Which ones rank the best, and how can mill be a good tool in EDH
In a mono-color deck, it's impossible to be color screwed (assuming you're not playing an absurd amount of colorless lands for some reason), and in a two-color deck, it's pretty unlikely that you'll get color screwed with a properly built mana base featuring a reasonable number of dual lands and other types of ramp / fixing
Inspiring Leader and Far Traveler are great if you want to keep it mono-white, its hard to go wrong with Candlekeep Sage for card draw, and Agent of the Iron Throne adds potential aristocrat synergies
Being a Special Guest printing, the supply of this wont be particularly high, so it wont drop the price of base versions much
It redirects any damage it takes to another target and prevents players it damages from gaining life for the rest of the game, making it a perfect finisher for decks like Mono-Red Aggro