Well argued but inaccurate in places! Some very dodgy analysis of the part played by the GR 3 in the Falklands (they were sent south mainly as FRS1 attrition replacements, remember, and weren't needed, and had they not done the low level BAI then SHars would have had to - a role in which they proved equally vulnerable). The SHar won the Falklands, but it has proved less vital in all subsequent operations. The GR3 did rather better than you infer, and the GR7 is anentirely different proposition, with a heavier warload, longer range and a genuine night attack and PGM capability, all capabilities sadly lacking in the SHar.
Also cutting back EF procurement from 330 to 250 would certainly save 'loadsamoney' but since the number being procured is 232 to support an active fleet of about 140 are you suggesting that we buy more?
No-one argues that the SHar isn't a great and useful bit of kit, only whether it's worth retaining in the face of other, more versatile and more useful priorities.
And we do have allies who can provide this level of air cover .............. if we need carrier aviation at all.