@BigMacAttack8u I see some idea of Lifeline's shield having 100hp. That's not the same as a full revert to how it was pre-nerf. Basically 100hp is just the same as no shield.
Gibby could easily do without a gun shield (he's already got fortified) and fast dome-revive, which would serve as a tiny Lifeline and Newcastle buff at the same time. I'm not sure if it would be enough though, but it would be a start.
Seer doesn't need a replacement. He could however trade in his passive for a larger tac cone and larger ult AoE, cooldown times, whatever. He's got enough wallhacking without a passive. Or they could just, as have been suggested everywhere, allow Pathy, Ash, Rev, and any future artificials, to not show up on his heartbeat sensor, so he can't just 100% rely on his broken passive.
I do also believe I have, semi-jokingly, suggested in the past that Lifeline's sorry excuse for an ult, could also work as an anti-scan device. Which now, as the scan meta has gone completely overboard, doesn't seem so silly. It would be a good buff and would probably make her viable in ranked where scan characters run rampant.