Even though it might seem basic, the most important thing to recognize when playing astral druid is knowing whether astral communion is playable or not, and in the latter case realizing that the game is not over just because you couldn't. Generally a turn 1-2 astral is a must if you have the means to do it, regardless of your hand quality. Turn 3 and onwards, it depends on current board state and aggressiveness of your opponent's deck, though turn 4+ astral is usually a bad idea. You will generally need to mulligan for astral/innervate/wild growth for obvious reasons.
Some notes on cards that differ from other versions of astral druid:
Curator: this card pulls either alex or DW, both high impact cards that can decisively swing the game in your favor. Sadly, you don't get to choose, but both dragons are powerful enough to warrant their inclusion.
Tomb spider: Aside from being pulled alongside a dragon by curator, this card helps patch up gaps in your curve, and is a better-than-nothing 4 mana play if you were unable to draw or play astral communion.
Master jouster: I always liked this card in astral druid, even though he hasn't been too popular in recent lists. With how many aggro/midrange decks there are right now, his effect will trigger very often, making it a reliable 6 mana 5/6 divine shield taunt.
Bog creeper: why this instead of AoW? 2 extra health on aow is not worth much in this deck because the main way your early game big taunts will get removed is through hard removal such as hex/deadly shot/sap. extra attack on creeper gives it better trade against certain minions and pressures enemy taunts/face more. It also works much better with y'shaarj.
Ironbark: this card is MUCH better in astral druid than people give it credit for, especially after y'sharrj was released. Of course, it is screwed by hard removal as much as any other big card, but your opponent will be hard pressed to come up with answers for so many taunts. Ironbark is the highest cost taunt in the deck that is still playable on the turn you draw it off of wrath, and is an excellent pull from y'sh.