Type 82 Destroyers were designed as area defense ships for the next generation carriers, but when the Wilson government cancelled them so were the type 82 destroyers, although one was built HMS Bristol.
When the last RN carrier was scrapped with catapults along with the Gannets that provided airbourne early warning radar, their was much criticism saying they would be missed and so it proved in the Falklands conflict with HMS Sheffield and HMS Coventry both being lost in their role of early warning defense pickets. There was the emergency development of Sea King helicopters with a search water radar in a dome of the left hand side of them. they were developed very quickly during the Falklands conflict but weren't operational before it ended.
The future with only having two carriers is that it will be difficult to always have one available, which is why you really need three. As you will typically have one operation, one undergoing a major refit and the third in port and probably undergoing a minor refit.
The problem with the type 45 destroyers is that we don't have enough of them and they currently have no sea defense capability, where they were designed to be fitted with US Harpoon anti-ship missiles but they ran out of money so they have never been fitted.

If you look at the procurement of most weapons systems these days because it is so political with attempts to share development with other nations especially in Europe, the whole system is an expensive dogs dinner, littered with cancellations and disasters.
The problem with fitting the Elizabeth Class carriers with catapults and arrester gear is a case in point. They are big systems that you just can't add on willy nilly to a party built ship and the latest electric catapults would have required the redesign and upgrading of the ships main generators.
So we are stuck with the VTOL F35 with all of its payload and range limitations. It is going to be interesting to see how the F35 performs is real combat as it is not a mix it fighter like the F16 and F18 it replaces with a relatively slow turn rate, where it relies on stealth and missiles for the upper hand.