On the one hand CVF/QE (CVS was the Invincible class) is huge with a vast flightdeck, so if you're doing mixed ops that's certainly an advantage, and in space terms I doubt we'll be any worse off than now in most circs. But using CVF partly as an LPH has some obvious downsides, aside from mixed ops being inherently more difficult.
One is the occasions when you need to surge the FW element (assuming you have enough airframes). With one vessel in commission, that rather limits your options. Another is sending such a high value asset into harm's way more than you'd really want.
So yes there's a strong case for adding an Ocean replacement into the mix, but even in these heady 2% days the money and manpower stretches only so far (and in the case of manpower, not very), so we make do.