While i do like the weakened revive mechanic on LB2 as suggestion, alternatives might be welcome.

So here an alternative: LB2 gives players a very high resistance on their last hitpoint so they technicaly for a moment cant be killed (except from insta kill mechanics). While it heals them with it. Then when it goes bad, you at least provided the teammates with some survival time, which might be enough to revive a dead tank and save the party that way. And even though this competes with the tank armor mechanic, 1hp is in the end not going to allow you to survive very long (and above that it doesnt protect anyway).
Sure, its not as strong as a revive, but avoiding death would negate the need for reviving.

And maybe instead of reviving everyone, it only revives those that died x seconds ago. Making it unlikely to revive everyone, but very reliable upon reviving the tank if that is needed.