To be honest, I don't really follow the development of the Romeo that closely now. I hadn't heard about any ASW issues, but there was a big debate (which may still be going on) about what radar to put on the thing. Initially it was going to be an ISAR, which is a pretty kickass radar. Then it turned into an upgraded version of what we have now; standard "tron goes out, tron comes back," but in technicolor.
A huge issue was the cockpit and software design. It was supposed to share a common cockpit w/ the Sierra, but the Romeo version basically didn't work. Since the Sierra was pretty much ready to go, and the Romeo was holding up everything, they decided to split them and let the -60S hit the fleet. Since they were dicking around w/ the cockpit on the Romeo, they also started to debate about the software and interface. One camp was advocating a Commercial Aviation standard (basically a hardware interface that the big boys use...EFIS, Flight Director, etc). But that was deemed too costly and time consuming, so they went w/ a different interface. As a result, from last I heard, is that now you have 2 big LCD displays per pilot, and some backup instruments. The problem now is that you always have to have one display showing the engine intruments, and another showing your primary instruments, so now you're down to two displays. Well, you want your copilot to back you up, and you're copilot will want to back you up so you don't kill him. So now one of his screens is going to show the instruments. Now you're down to one screen for the tactical/sensor display........which is what we have now.
There's some other issues (big ones) that are popping up like weight, which is coupled w/ overloading the airframe w/ sensors (much like the Bravo is now). Not sure how they're working through these, but I would guess it will continue to be a problem.