Currently, it's possible to use your own spark of life to revive a teammate. However, you have to go into the side menus for your party members. As far as I know, these menus lock you from moving, making it really difficult to try to revive a teammate while you yourself are fighting. What I propose is that one can revive by attacking over someone, just like the old hp revive. However, since people will want to be more careful with their Sparks than their health, there should be a really quick second click to confirm, like the energy gates.