Every single consecutive death within the same level should double the amount of Sparks of Life consumed upon revival. The current event has made it pretty clear that if nothing is done, all future content will have to be designed around infinite respawns. Facerolling through the stupidly unfair fight a few times still has me left with hundreds of the damn things. Mission success should not hinge upon grinding for limitless respawn tokens. The old system of energy revivals quickly got so expensive that the player had to actually admit defeat, something that is no longer true.
Oh, heck, if you wanna be crude, you could just cap how many you can carry to 10 or something and only allow more to be purchased at Arsenal Stations. If your goal for the things was to remove Energy from the system, that'd force people who are actually good at the game to occasionally purchase some too. Something needs to give either way.
not everyone has bajillions of sparks. I have less than 10. besides, even before guys that had bajillions of energy could blaze through content.