Im specifically debating:

1) adding more 1 drops (something like Wasteland Viper Spire Tracer or Gladecover Scout

2) adding Slaughterhorn maybe to replace the Giant Growth

3) adding 2 drops Kalonian Tusker or Deadly Recluse , possible swapping with some of the Call of the Conclave

emm, voice of resurgence?

Unfortunately I don't have the money for voice.

There's a interesting combo with Scion of Vitu-Ghazi . Turn 4 (or turn 3 with ramp) end of turn Advent of the Wurm into next turn Scion gets you 2 Wurm tokens and another 5 power on the board which is pretty cool.

Yeah I've looked at scion. I don't know how much I like it tho. I mean, for 5 mana I would almost rather play Advent of the Wurm and then Wake the Reflections . I'll look into it, maybe playtest it. I'm also looking at some other finisher.