Archangel of Thune can be a beating with Oloro. Erebos, God of the Dead can also be good since you're gaining so much life and maybe Obzedat, Ghost Council . Path to Exile and Coalition Relic are two more cards yoou might take a look at.

I think it may help if you use your life total to get a full board of creatures, that might help you finish off your opponent faster, if you don't draw your Felidar Sovereign or something. Ajani, Caller of the Pride is not a bad planeswalker either, I think he might work well with this deck and he's only 3 mana. Also maybe Angelic Accord ? This is on turn 5 but with this deck I feel like you can get a 4/4 flyer almost every turn given that you already gain 2 life off the bat from your commander. Hope this helps

@Dandelo Archangel of Thune was near the top of my list to get, and Erebos instead of Karmic Justice. I also need to include my Wasteland , Scalding Tarn , and Misty Rainforest . @mtgchoi I considered Angelic Accord, and it almost never popped out more than one angel.