So as an operator, I ask "do I want STOVL and how much is it worth?" and "I probably want to exploit stealth - but am I better off with F-35, or with Rafale/ASH levels + good EW + a few very stealthy UCAVs?"
I think that's two great questions LO but isn't the problem twofold
1. We are where are
2. That would depend on the advances in enemy AD systems over the next couple of decades
On the STOVL question, surely it comes down to the degree of flexibility you want for the price you are willing to pay for it and the true answer to that flexibility appetite is going to manifest itself infrequently
We can point to a number of instances ourselves where STOVL flexibility was in the 'more than nice to have' column so for the UK, a mix of Typhoon and F35B, plus a longer term goal of the mythical UCAV, seems like a pretty sensible option