Angels and paladins – how to use them? There are also discussions about them here.

So, that's the whole point... If you've leveled up Logistics to Tactics, or found some good boots, then of course, you take Isabella. But if you don't have those bonuses, then go with the Paladins... Plus, Paladins have the Lay on Hands ability, which is very, very important (I'm not talking about healing, but about removing enchantments).