As I have seen from many players there is quite a large number of you that have a horde of sparks.
As a player who calculates how much I would gain by reviving and more often than not deciding not to revive I still seem to have a terribly low number of sparks. (single digits)
Aside from reviving at the very end of Vana runs, event bosses, and reviving the sparkless before the last arena prizeroom I never use sparks for casual play.
Am I doing something wrong when it comes to sparks, am I terribly unlucky when it comes to prize box sparks, or is there something wrong about how I judge whether or not to revive?
What are your criteria for using sparks?
The missions give you over 200 Sparks of Life, right? 250 maybe? From there, my Sparks of Life have generally gone up. I use them only on special occasions, such as events (tortodrones) and Shadow Lairs. I might use one at the end of an FSC run, if I died and my team needed me.
So you and I are doing the same thing, except perhaps that I am dying less than you are. (I don't say that to be mean.) Stay the course, and play safely. :)