Personally, I couldn't care less for the Deva, but hey.
I think you did pretty well with the Shardmind conversion though. One thing I'd like to say: the shard swarm is kinda...meh. It's kinda pointless. 1d4 is the damage of an unarmed attack, kinda pathetic. You restrict your movement to 1/2, and you can still be attacked. Not to mention an effective 24 hour cool down? There's the slight bonus of being resistant to one type of damage (which is really quite powerful), but is offset by it's vulnerability.
There are a few ways to make it a bit more useful. One: you could explicitly say that this movement allows you to move through small cracks in doorways and such; as well as explicitly saying that you don't provoke attacks of opportunity for moving in this way. (Makes sense as most creatures don't expect their opponent to turn into a swarm of floating crystals and move past them)
Two: You could, instead of damage, have it force some sort of save (perhaps dexterity or wisdom), or have all creatures you pass through to treat all their targets other than you as having concealment until you reform. (They can't see them past your swarm) You don't provoke attack of opportunities while moving in this form, but they can attack you as normal.
Three: Require a short rest, as opposed to a long rest. (If nothing else is changed, this doesn't matter too much, as the ability does nothing, save maybe from protecting you from a fatal blow of a piercing weapon [and even then, you're still provoking AoO for running] )
Four: Say that you are virtually untargetable until you reform, but the square where you are can be targeted by an AoE ability, and you'd take the regular damage.