I should have been done with this game a while ago, but the liberate/overthrow missions (which I assume are optional) remain fun despite being the same "destroy three blockades" shit every time. The ones where you help yellow gang fuck up purple gang are especially funny with a grenade launcher, because after the third blockade you can just shoot one well-aimed grenade at the bullet-sponge purple gang boss to finish it immediately.
I think I'm more than halfway through the main story missions.