Biggest issue for me is their HP pool.
Reasons: I can one-shot most artys with my T4 Onager (JA) but I can't one-shot tac cruisers while they are higher priority targets than artys. Plus they are most of the times hiding behind walls whiles artys have to expose themselves (if they stay at max range, they get killed by corvettes because they are alone).
Tac cruisers have to be in the middle of their team so it's harder to kill them with a corvette, and impossible if there is more than one healer, because they just heal each other.
So I don't see why they have way more HPs than artys (+5000 or 10000 for the Oberon line).
As AnalProbe (great nickname lol) said they shouldn't be able to survive in fights that long, briefing or not.

TL;DR: nerf their HP pool / movement speed / adrenaline shot so we can actually kill them.