These are mostly up to the GM. I'd personally say yes to changing NPC Morales and recruiting monsters under certain circumstances, but different GMs may handle this differently.
With NPCs, their stats are meant to be written in a simple and quick way. You could give them a full PC style set of Abilities, but this would take more work and slow the GM down when they introduce a new NPC. The recommended thing to do is give them specific skills (e.x. Climbs Walls DR 8) when relevant, and then you can modify these further with circumstantial bonuses and penalties when appropriate. But if an NPC is really important, you could give them Abilities instead.