Survival advice regarding imbalanced guard and glancing blows on chieftan

For this league I decided to go really tanky. So I am planning on running chieftain with 10 to 15k armour, 25 to 35 % physical damage taken as fire, 50% of cold and lightning taken as fire, 80% fire res, 40 % block chance, molten shell.
I can add imbalanced guard and glancing blows, but do the cons outweigh the benefits, and should I run the new banner skill?

GB basically transforms avoidance into mitigation. In your case with block on the lower end, as long as you go with multiple endus, and especially if there'll be + max res, then this notable looks like a pretty good choice.
With or w/o recovery on block.

Imbalanced guard is a no-go with builds amassing endu charges, with moderate to high amounts of armor.