Engines -
We're clearly on opposite sides of this issue, and I will accept that sometimes I get a little frustrated. However...
On the Marines: I don't see a lot of honesty in Marine leaders talking about "11 more aircraft carriers" or pooh-poohing the very real problems that the B has (to the point where even the Brits have bailed). This is very top-level: The Marines know the power of memes, simple ideas that get people's attention.
And it's not just the B: There's the EFV, a classic case of bad requirements leading to bad results, a project that should have been killed long before the deed was done. There's the V-22, which is very impressive - but is it really worth what it costs compared to a helicopter? Has it really been worth the 25-year influence on US rotorcraft R&D? (If I'm AgustaWestland or Eurocopter, at this point I yell "Yes, a thousand times over.")
The F-35A/C are respectively CTOL and CV versions of the F-35B. The STOVL/LH-compatible requirements dictated the weight, the single engine, its size and location, internal layout and overall dimensions (with an awkward scaled wing and H-tail for the C). As for saving money, the projected cost for the F135 is still more than two F414s, which provide more thrust and weigh a ton less.
As for keeping the program affordable... If this is what we call affordable, we're in trouble. Indeed (aside from the development cost of the engine) the B has cost the program dearly, through the weight gain and SWAT.
I have yet to see the Marines' "solid and well argued CONOPS". Where is the situation in which you need a sea-based supersonic stealth fighter, but don't need tankers/AEW/EA? How do you forward-deploy an F-4-sized aircraft on to 3,000-foot strips, even accepting that its exhaust is not an asphalt-removing system?