S-70B-2 "upgrade" to Utility cab
The core avionics issues are just that - core. It has little to do with sensors or weapons, but basic flight management systems. Many of the components that make up the avionics in this aircraft are now, or soon to become, unsupportable. The only way to make these cabs useful for fleet utility would be to undergo significant work (=lots of $'s). Even then you will still have old airframes. Bringing in the Romeos will not address the Fleet Utility issue - they are not built for that and cannot readily do ANY utility tasks.
Looks like the MRH90 will be busy at sea.