The biggest problem with the QEs is that they are powered by gas turbine/electric propulsion.
They could not have had steam catapults fitted, because there is no steam plant to generate steam (unlike the US nuclear carriers). And the electro-magnetic plane flingers were not available when the ships were first planned, need huge amounts of electrical power, and are bloody expensive (being current US technology).
If the design had been built around four or six Astute sub. reactors, they would have had either steam or surplus electrical power. But some bleeding hearts had decided that the UK should not have nuclear powered surface warships. So we have ships with limited range, reduced accommodation for crew, provisions, weapons and aircraft because of the need to have J-fule bunkers and fresh water tanks.
IMHO, they are seriously compromised ships, along with their built-around a-single-weapon system escorts, the Type 45 destroyers. I though the navy had learned this lesson after the County class and Type 81 large destroyers of the 1960's.