Shard of Bravery is very scarily fast in Cremation rushes atm. I'd expect a normal response to that to be, "So what? Your opponent's drawing cards at the same rate as you are!", but the problem here is that SoBe takes away nearly all of a Cremation rush's former inconsistency thanks to increased drawing, and can produce quanta much more quickly than most decks unless they're using another similar quanta production accelerator. I've been using a deck with Crimson Dragons and Seraphs with Minor Phoenixes and it's easily getting 4-5 TTWs consistently; not having enough quanta through Cremation alone rarely matters when you can expect your deck to win in 4-5 turns regardless. No PC, though. But if this is how fast it is in a Mono Fire based Cremation rush, I'd be terrified to think of what it's capable of in a Rainbow based Cremation rush.
I honestly think it needs to be bumped up to 3 as 2 would likely still be too cheap.
Honestly, this was here and even better before this "nerf". In my opinion, the game needs a super fast rush, and sobe immorushes are just that, very frail and fail to things such as an early dim (thats why I run sobree), but they actually took a bit of a nerf in immorushes, and a buff in other decks, which in my opinion is how it should be. For example, all of my immorushes run without towers/pends, and a seraph is 1 turn + 1 cremation. If you are using SoBe, then it takes 2 cremations to get out a seraph, and you might as well be using Rubies. As slight as it is, it's still a nerf. For the record, these rushes didn't really dominate CL (a good guage of upped meta), as they can be countered pretty easily, and SoI rushes were just as competitive. I've been outrushed by powerful wyrms with this, as the faster you draw, the faster they draw.
The reason I dislike its current speed is that it makes Mono Fire faster than all other Mono Elements by a significant amount. Mono Fire based Cremation rushes before SoBe was introduced were found to be around 6 turns to win on average with Mono Life close behind and some others not far after as well. I have managed to pull off 3TTW with SoBe in its current form, and further testing shows that adding Explosions doesn't interfere with speed much at all. I still need to test how changing this from a Mono Fire to a Rainbow Cremation rush changes the speed, but I'm actually not expecting a very noticeable increase, if any, in speed and the Mono Fire rush might actually prove to be more resilient, honestly.
There's also the fact that Seraphs can become immune to CC after the first turn, which further increases the opponent's reliance on the first draw. I've also had as many as 3 Pandemonium used on me without all of my Seraphs being protected and still managed to easily win in 5 turns. And contrary to your statement, a mix of Cremations and Fire Towers allows Seraphs to be played without 2 Cremations being needed while if excess quanta exists it can go to playing another Seraph or a Dragon. Is it counterable? Sure, but I don't think that that's enough justification to leave it as it is.
My understanding of the CL meta is that a significant portion of it is shard based. How do the latest Shard changes affect this, would you expect?
However, I will admit to my analysis being faulty given that I cannot accurately assess how it fares in PvP until that ability is enabled. I never really used SoBe in Cremation rushes much before the latest change, but I would imagine that the change to exclusive Fire quanta cuts down on its speed a bit given that it can't make any use of the excess quanta produced by Cremation. If 3
proves to be too high of a nerf then 2
at the least should be minimum.