Why does the Navy need something better than the SH quickly? What has it not been able to do? You do realize the limited role that the SH has been deployed in thus far, right? It has been very effective in its role. I'd like to see anything you might have, other than idle speculation, that the SH is not filling its role well.
What?.... doing strikes over dirt where there is no air opposition?
Carrier Air has to be the ultimate big stick that walks in and has influence over an area. That job is harder with SU-27 and 3x and even the occasional SU-24. All of which can go around a SH if the opportunity presents itself. The circle of influence around the carrier is not only shorter, but also re: A2A.... more limited.