It's almost impossible to get peace when you want it in a Total War game. Depriving a faction of money will just make them throw a couple levies at you every turn instead of a whole stack.

When I roleplay peace, I'll just auto_win battles against the faction I'm "at peace" with using a faction of local easily retrained units. I'll also often use the move_character cheat to move armies away from my borders every turn, making them remarch the same march.

There really isn't any way of getting gaurenteed peace unless you live on an island in RTW.