Cannot resurrect for X time is probably the best and only workable solution.
Other than that I say leave it as is. Right now it is just quite useless with War master powers around. I am fine with that. It is not an equalizer spell anymore because if you are outgunned the zerg would kill you before the incantation is over or a conju will rez before you. If you do succeed, they will be back with port and HOTW in no time flat .
A waste of 5 points any way you put it. You might be better off putting the 5 points in Vitality absorption