The thing is though modern naval warfare relies on multiple networked platforms so except for flag showing, border protection and low intensity multinational security missions, our ships do operate in task forces. In fact our acquisition of almost defenceless LHDs requires our use of task forces to guarantee their security in all but the most benign circumstances, one of the justifications for acquiring the AWDs was the need to protect the LHDs (and other ships) when deployed on anything other than a friendly visit or HADR.
The thing is the aircraft, even if only helicopters and perhaps UAVs, operated by even a small carrier contribute significantly to any task force they belong to, they are far from a passive element. Add Harriers or F-35B and possibly AEW and you have exponentially increased the reach of the task force you need to have (even without a carrier). A carrier provides an outer layer defence for the taskforce and a long range surveillance and strike capability. Instead of several escorts in the taskforce you can have a couple, instead of two high end helicopters per escort you can have one and maybe a smaller multirole type or a couple of rotary UCAVs, with most of the TFs helos being on the carrier and that vessels facilities being available for deeper level maintenance for the ship flight helicopters.
You still have submarines, they are a vital element of maritime doctrine, you still have the increased numbers planned. You still need your AWDs and some high end ASW escorts (something we have been short of) but then, if you decide to have a small carrier, you pay for it by reducing frigate numbers. This, incidentally is precisely what happened to get the LHDs and planned extra subs, planned surface combatant numbers and capabilities were reduced.