Sounds kind of interesting, but frankly I want to get away from this mindset that making a mediocre movie is acceptable as some kind of setup for "my Wrath of Khan". IMO if you make a mediocre movie, you get booted from the franchise, as it should be.
Sure, give the next guy the chance to start over and make his mediocre movie instead. Then the next guy...
I mean, your statement doesn't actually have anything to do with how anyone involved - studio, directors, etc - actually approach these projects.
"Ah, this is my first time at bat so I won't try that hard. 'Mediocre' is good enough, because I'll do really well on the second one. After all, I know that they'll keep me on."
Yeah, that's the "mindset" and those are the expectations that motivate the way things are done.