I would have agreed that the Harrier's situation seems a lot more awkward than the GR4's. JFH is simply too small to sustain any sort of long term op, as we've seen with HERRICK, so what is it really likely to do of use in the medium term as we're trying to save money?
I know that the previous CAS was rumoured to have offered the Harrier as a sacrificial lamb in the next round of cuts, but was shouted down by the Navy. How about a compromise?
The Harrier's only real USP is its ability to embark, so disband the entire RAF side of JFH and give the whole lot to the FAA. They can keep the NSW or form 2 unique squadrons again, and use it to cover training with the existing carriers and to maintain their cadre of FJ qualified pilots until JCA and the new carriers arrive.
Decimating the F3 force early left us with a glut of pilots who seem to have found jobs alright, so I'm sure that 1(F) and IV(AC)'s pilots wouldn't be left hanging.
You could disband Naval Fixed Wing Standards (I would have thought with FAA FW aviation being so small now, there's no reason at all why they couldn't be standardised and examined by CFS along with the RAF?) to save the FAA some money, and if the FAA Harrier force had less to do they could pick up on some of the Hawk roles. You could even move them all back to Yeovilton!
FAA gets to keep some element of FJ aviation, although one that's unlikely to be able to support any sort of deployment. RAF saves a bucket by effectively getting rid of a whole fleet, and frees up a bunch of pilots with some recent operational experience who might be considered very useful in the GR4 or FGR4 worlds.
We lose the ability to send the Harrier force on another operational det, but it looks unlikely that they'd be doing that anyway.