Questions that could be their own discussion thread, for certain, but not here, unfortunately.
Frankly, if I'm being honest, I don't think buffing tanks is the end of the world, I just know it won't end there. We'll hit 5.2 and 5.3 and we'll see this thread again, because the core problem is that tanks, even as fun as they can be at times, are still just extremely shallow.
A potency boost should be seen as patronizing, not as the solution, because that would just be a "Quiet down and enjoy your 800 more damage per hit".