Mulligans
General Mulligans
It is almost impossible to list a general mulligan strategy. Unlike with most combo and aggro lists, your mulligan choices will almost entirely depend on your opponents class.
Aggro Mulligans
If your opponent is Shaman, then keep BGH for his fatties. If it is paladin, then keep Ravaging Ghoul.
Combo Mulligans
Assume Druid is Combo. Against AK47 (Star Aligner) you just want to armor as far out of range as possible and try to clear immediately afterwards. You might be able to sneak out a win against Togwaggle by mercing your own Deathlord and hitting Togg or Aviana, but barring that you just lose to Tog.
Control Mulligans
Your most likely control matchups are Big Priest and Warlock. You need your single target removal against both.
twitter.com/raist819/status/1046315800804687874
This is a control deck that works very well in the current meta. You auto lose against Togwaggle, but you can armor yourself out of reach of the other Druid decks and non Exodia mage, you have almost as much removal as Big Priest and Reno Warlock have threats, and you have an oppressively strong advantage over the popular Aggro decks Even Shaman and Odd Rogue
Azalina Soullthief is replaceable. She is situationally strong, but is often dead, so don’t craft her just for this deck. I’d replace her with a Supercollider if you don’t use her. The Direhorn Hatchling could easily be a second Dyn-o-matic and I will probably make that change myself next season
The best advice I can give for any deck is to learn the matchups and mulligan aggressively for your strongest matchup cards.
I like your deck !! Thx