I mostly focus on bomb/sword combo. Would Chaos Cloak be beneficial for me? or Divine Mantle is always the way to go?
Divine Mantle or Chaos Cloak?
First, you don't want to wear both Divine Veil and Divine Mantle, because then you'd have no normal protection. Second, Divine Veil has a fiend bonus, while Divine Mantle doesn't. Consequently, there is almost no reason at all why you'd ever get Divine Mantle. (Okay, you might get it if you really want one piece of Divine, and you really want to pair it with a certain helmet. But that comes up rarely.)
In contrast, Chaos Cloak is one of the most powerful armor pieces in the game. There are entire threads and guides devoted to how great it is. Well, the defense is bad, but the offense is outrageously good. You want that armor.
normal damage isn't THAT critical in tier 3. I'd rather have NO normal defense than ALL normal defense.
And you can easily use sprite perks to mitigate the one status type you'll run into on any given floor (if you use chaos).
I'd recommend to mix one piece of each. Chaos is definitely better if you stay on the offensive, but it's weaknesses can be overwhelming on a first try.
Divine Veil balances it out well enough without having to resort to UVs. You could use it for a while as practice.