Holy Sheltron/Intervention isn't as powerful as they are made out to be, you have to keep their buff rolling not by choice in many situations, because of points gains, the ability isn't free, and you need the second one for the busters. Paladin has always generally lacked self mitigation, it's perfectly fair. Reqs healing? Not by choice, Paladin has a forced rotation requiring. Out of more player throughs, Gunbreaker is shown to be a better main tank, it's only bad at positioning bosses.
HOC is a strong ability, a short mitigation and only gets proper value if the target falls below 50% HP, but it is stronger than TBN, Gunbreaker has a lot of cooldowns.
Bloodwhetting/Nascent Flash are extremely powerful abilities, which I would no doubt these two will get healing nerfed, they're basically I don't need a Healer when active, Thrill of Battle adds more boost to them. Bloodwhetting/Nascent Flash can be popped whenever you need it without drawbacks.
TBN is intended to soak a heavy attack, that's what it's designed for, but I do agree the punishment needs to go with an increased cooldown. You can't have Oblation operate closely to the other 3, and have TBN, that's incredibly overpowered.