Best color is, IMHO, White. Three common removals, none of which suck, Healer's Hawk as the best common 1-drop and other nice creatures, good lifegain and fliers, access to best guilds.
Speking of which, IMHO, best draft guilds are Boros and Selesnya. Izzet and Dimir are okay, and Golgari suck.
Boros is very fast. And it's creatures grow big enough to eat green monsters. It also has the most removal among the guilds. And Boros Lockets take away it's biggest weakness - resource production. Boros has one strategy for all occasions - so, as an additional benefit, it's very simple to play.
Selesnya is efficent and adaptive. Against fast starts, they jam up the board with big creatures and lifegain, and, during the latgame, they win with mass pump and/or fliers and/or token engines. Against slow starts, they rush in with big creatures and pump spells, and close the game up wth, again, mass pump and/or fliers and/or token engines. Note that actual token production is optional and incedental to their plan - don't play the one-drop Marshall and Sworn Companions and Hunted Witness over good cards just because they make tokens once or twice.
Izzet is powerful but unstable. They can kill opponents out of nowhere with aggressive cards, and win the lategame easily with control cards. The first problem of Izzet is that they can't control which way their game will go - the most adaptive color combination proves to be very non-adaptive, with card selection and card draw being at uncommon or costing too much mana. The second problem of Izzet is they don't have lifegain or cheap common removal, which means that they will often fall prey to Boros or Selesnya assault. Also, they tend to run out if creatures rather quickly.
Dimir is synergistic but slow. They have all the tools in the world to win the lategame (card advantage, filtering, counterspells, hard removal, flyers, beaters, life drain, etc), and even some nice stuff to get to it - Dead Weights, Poisoners, Children of Night, Dimir Informants, Unexplained Disappearences. Their first problem is that their early cards cannot really stop the concentrated aggression - only slow it down. Their second problem is that they rely on Surveil synergy too much - answer their key pieces, and see them desperatly pray to draw their flyers - which are the only plan B for Dimir. I have won two games against Dimir due to them milling themselves out, because some people really like Disinformation Campaign and really don't like Enchanted Survealence. Don't repeat their mistake - if you run the first, also run the second.
Golgari are, IMHO, criminally underpowered. Their supposed strategy of filling the graveyard and getting benefits from it relies on a LOT on synergy. Sadly, they have NO good common enablers and ONE good common payoff. ALL of their other good payoffs are rare. Don't play Golgari, if you can. If you can't, because your first packs had phenomenal green and black cards, DON'T BUILD GOLGARI AS A GRAVEYARD DECK. Build it as a generic Black-Green Midrange deck. They have nice efficent creatures and removal. Consider splashing into white for more nice creatures and removal.