The elephant in the room for me here is AEW with the pressurized cabin and 7600m ceiling, which is not explicitly stated but I guess it's what you could call maritime surveillance in a more general sense (which does get mentioned). There used to be a proposal for a new AEW version of the AW101 using a pair of APG-81s in panniers - this should be within the payload capability of the AW609 and offers commonality with the F-35B. Though with graceful degradation the antenna/transmitter of a modern AESA should be essentially maintenance free, I'm sure there are cooling, power supply and computer LRUs where parts/tools sharing would be worthwhile.
Too bad they went for the PT6 over the T700, else even the engines would have commonality with the AW101 and NH90! Endurance is probably not going to improve much if at all (maybe shorter transit helps?), so the logistics of 24/7 AEW coverage are still challenging, but that ceiling is a potentially huge benefit for STOVL carriers.
UK Apache replacement held up by AgustaWestland, BBC report states