I'm always glad to see new cards in the works, and here's my two cents for anyone who cares:
Shard of Conscience: Balanced, by the fact that it takes quite a few of them to have any noticeable impact, but if you do get that many, the impact is huge.
Shard of Focus: Overpowered. I've already discussed this one in the past in this thread; it needs serious nerfing, or every deck will be based around using it or countering it.
Seraph: I love the concept behind this card, but sadly it doesn't make thematic sense in fire (a seraph is essentially an angel) and it's also probably too powerful with that high of an attack. I think it's also too similar to phoenix and crimson dragon, because they are both very heavy-hitting, low hp creatures, and the divine shield makes it hard to kill like phoenix. I'd love to see a slightly nerfed attack version of this card, only in another element. I'm also really liking the art on this one.
Just out of curiosity, why did seraph get picked as a card out of all of the ideas on this forum? Seraph definitely has things going for it, but there are some really brilliant cards in the ideas forum that fit needs of certain elements far more than this one.