IMO this depends. If you're not running a bunch, you can annex your way out of strong duchies + nobility integration, and sometimes the marginal DIP cost of that isn't too bad if they're not big...especially if you time it so that adding > 50 absolutism ends the annexation so you're getting most of the benefit.
As for monopolies, giving them does hurt income, while giving loyalty and mercantilism. Mercantilism isn't useless, but it's also not amazing. I tend to give monopolies on things I don't have a lot of so I get the loyalty boost + mercantilism w/o losing much cash (20% income over a several year period on almost nothing).
OP's issue is not planning ahead in a few ways. One is that influence is simply too high relative to loyalty. That's bad, it makes it hard to revoke privileges. The other is simply not revoking them with enough time before absolutism.
If you're willing to hurt reform progress a bit, you can swap into a government that takes away nobility, which will also take away its privileges and distribute its estate land to the remaining categories. For the others, there's no choice but to boost loyalty and revoke them.