White is a power house now and everyone seems to be sleeping on it. The greatest thing about white is it's answers for nearly any style of deck.
Let's start with the one drops:
4 Soldier if the Pantheon. Does anything else need to be said about this card? It's a 2/1 with multicolored protection and it can net you life.
4 Brave the Elements, protection and a win-con all rolled into one cheap card. An absolute blow out card that is the bane of all of your opponents.
Two drops:
4 Precinct Captains put the pressure on opponents quick and early, generating tokens is also great for convoking out Devouring Light.
4 Nyx-Fleece Rams. One of the most underrated cards in the meta in my opinion. It will single handedly shut down those aggro and sligh decks running around as well as netting you 1 life a turn which against burn is a huge set back. When games come down to the difference of a couple life points between losing and winning you'll be glad to have had this little guy out in the field since the beginning.
Three drops:
4 Banishing Lights, great removal all across the board. It hits big creatures, pesky planeswalkers and oppressive enchantments. Not much else to say.
2 Devouring Light, I'm currently experimenting with this card but I'm really interested to see what I can make of this with a surprise Convoke blowout.
4 Brimaz, king of Oreskos is a threat on the board pure and simple. Generates dudes for the army and chump blocking. The card is pure value.
2 Spears of Heliod, between Precinct Captains, Brimaz, and the raise the alarms in the sideboard, the Spear can make or break some games. It's other ability is also very relevant and can leave some of your opponent's threats at bay.
Big stuff:
4 Souls of Theros, this card is the shiznit. It passes the vanilla test just by being a 6/6 for 6, it has vigilance and it can pump your team to victory. I love it. It's ability is also relevant in graveyard which just screams value.
3 Elspeths, the nail in the coffin in most games. Standard has shown time and time again that this card might be the biggest threat in standard.
2 Mass Calcify, jund monsters? Mono blue devotion? RDW? Hex proof? Nice knowing you.
3 Nykthos, because this isn't a white weenie list.