The more I think about it the more I'm sure that Shard of Focus is not a good concept at all.
All other Permanent Controls are bound to certain elements (

and

- did I miss something?). With this Shard, any deck can have a Permanent Control. Though it can be used limited times, same goes for Explosion, Earthquake and Steal, and these can be used only once. Though the Shard can be easily destroyed right after it's been played, after one use it's hard to get rid of it. Also, this is compensated by the fact, that the Shard itself can gain many other functions too - most popular is Acceleration, but eg. Gravity Pull also works. Sometimes winning a Black Hole is a great advantage - frankly, I have a deck which uses one single Shard of Focus and that Black Hole's healing saved me many times...
So, Shard of Focus can be attached to
any deck and in many cases it eliminates the
only weakness of that deck. The only "penality" in this case is a dead card (if the deck has no

quanta).
For Permanent
protection there is only
one element; more precisely, one card.
As a Permanent Control creature, we already had Butterfly Effect, and lucky mutations.
We'd need another Shard instead of this. Or, alternatively, "redirect" Shard of Integrity to the

element, and give

eg. a "Shard of Protection". (Which could protect permanents or increase HP for all creatures, with an

bonus.)