Voice is nice and all, but I'd actually think you might have a better shot with this version than with Voice. I get it's resilient and stops people from doing stuff on your turn, but a 2/2 for 2 in an G/W aggro build really just is out of place.
I could see perhaps moving a few things around here but for the most part it looks solid and any card substitutions will be up to you and your playstyle.
Personally I'd likely cut 1x Boon Satyr and 1x Scavenging Ooze to insert 2x Spear of Heliod for that added little bit of pump to finish the opponent off, but that might be just me. I would also look into Precinct Captain in some quantity as T2 Captain, T3 Ajani with his -2 for flying double-strike, 4 damage, crap out two 1/1 soldiers is pretty good.
For the SB:
3x Mistcutter Hydra sounds about right as it's really your only shot against mono-blue. I would also suggest looking into Last Breath for the board, as it can deal with Master of Waves and Gray Merchant.
Sundering Growth strikes me as a solid option in the board given that you already have the charm to exile the gods. But only 1x? I would up this to at least 2x if not 3x.
Pithing Needle is suuuuch a powerful card at the moment and really should be at least a 2x in most boards these days. I would up the count if I were you as it can shut off PWs, Underworld Connections, creatures with monstrous, etc.
I will admit that I'm a HUGE fan of Trostani as a card and love her abilities, but I really don't think you need her in the board here. In the event you're up against an aggro deck and life is relevant, your stuff is bigger than theirs and you can play on the defensive until you land Unflinching Courage on something and just use lifelink for the win. So to that end, it's not like you'll need the added life gain or populate given that you're bigger and faster than most aggro strategies.
Rootborn Defenses is a card I'm somewhat on the fence about here. It seems such a natural inclusion, and I would probably leave it alone because it stops sweepers AND populates, but on the flip side, you already have Advent of the Wurm and Boon Satyr which allow you to completely play around wipes as though they're not even there... so to that end, I don't know if the defenses are necessary anymore.
In either event, you're sitting on a good list and will likely have some luck with it.