Escorting missions in Space Rangers 2 are the best ones, since the ships you are escorting can have it's enemies fought off quite easily, but not so easily as that they become boring.
Another example of what I call "an exception that still doesn't justify the mechanic". As in, yeah, I'd give up the handful of games where a certain mechanic was very good if it meant I'd never see it in its horrible shape in the 95% remaining games.