The thunderstorm change seems good; it was a rarely used card before, and this is a good way to buff it. It compares fairly reasonably to pandemonium, rain of fire, and dry spell, and I can see it getting some use, now.
The shards change makes me a little nervous, but we'll see how that plays out. In some cases it will be an enormous improvement, particularly shard of focus, but in others, it will make the card nigh unusable, while a few others will notice little to no change.
wisdom: basically no change, since you needed immortal creatures anyway. Other than flying glories, doesn't really nerf any decks, and that deck can just play aether mark in that case
freedom: nerfs a few decks, but other than maybe immorush with seraphs/phoenixes and freedom, mostly just nerfs silly decks
darkness: Small nerf to a few decks, but most decks using shard of the void used darkness mark anyway to speed it up. Only deck I can think of that this nerfs hard is my SS/miracle/purple nymph deck, and that's a very specific and rarely used deck anyway
death: Since shard of sacrifice costs 0, nothing changed with this shard, and it's one of the worst offenders of all the shards. I'd probably recommend increasing the cost; even something like 3 should be good enough, preventing nova/SN abuse to play it.
earth: Shard of integrity was a fairly narrow card already, so it didn't see a lot of use. With shards costing elemental quanta, I suspect this card will become pretty much unused, but I'll see if I can create something that still makes use of it. The days of 6 nova/6 SoI/18 any shard will be done, and that's a good thing. Decks using shard of integrity will probably have to be duos or trios, now. For example, something like earth pends + fire mark + SoI + SoB + whatever for you golem.
entropy: Pretty small nerf, since you were likely to be using a rainbow and/or lots of entropy anyway. It just means the SoSe will come down a turn or two later, which it probably would've anyway since you need to clear your hand to fill it up with that shard
fire: Prevents certain stupid OTK decks, which is a good thing. This change should be good/mostly unnoticed.
gravity: GREAT! Shard of focus will no longer roflstomp the meta.
life: Shard of gratitude will probably get very little use, even less so than now, especially as life has empathic bond already, but it will still have use in some creatureless decks that need healing
light: Probably a good change, but we'll see. It should also increase the use of the heal card, which is a good thing.
time: Very good change; prevents a lot of really stupid OTK decks like instosis and mummy/rt/SoR decks, both of which are bad for the meta. Probably one of the best changes, after shard of focus.
water: Not sure about this one; on the one hand, it's harder to play SoP, but on the other, it's much stronger. Time will tell on this one.
I think any balance issues at this point should be solvable by simply adjusting the quanta costs on the cards. Overall looks good; will playtest over holidays.
As an aside, any chance of future other cards, along the power levels of shield, short sword, etc? I like other cards, and would be sad to see the 'other' tab of my collection so empty.