I too have concerns about Shard of Power being too . . . well powerful.
I let's you rush any type of quanta while committing nothing to it aside from your mark and just a few cards.
A mark of
and 1 Shard of Power allows you to cast Fractal every other turn, without any other quanta sources. Since the shard only costs 2 you can easily drop them on your first turn.
Enough Quanta to fractal every other turn, or miracle every 3 turns, from only one card and your mark seems really OP.
Fractal decks are already really powerful, this card would make it so they don't have to slow themselves down with more pillars.