Not seeing how those are big problems, can you elaborate? Sierras land on every US Navy ship class and spend the night on Carriers, Gators, and USNS ships every day of the year. Every aircraft has its gremlins and quirks (aka Sierra's fold system), but there are some advantages to the Army tailwheel configuration like weight savings and tail rotor protection during brownout landings that offset the disadvantages in my mind.
They can land on the ships, but the margin of error is much less now due to tailwheel position. Having been in situations that required use of the RAST, I can say that it provided significant benefit for helicopters landing on CRUDES. Actually the Sierra is only significantly lighter than say a Hotel because the Navy sacrificed a few thousand pounds of inherent fuel capacity. Unfortunately the aft tailwheel design introduced some other fun issues like airframe cracks. To the point where once a crack is repaired and the frame member shored up, the cracks re-appear farther down the frame. The tailwheel doesn't protect the T/R. It does provide a bit of extra margin of error in TERF landing profiles for lazy pilots. However the older tail bumper provided the same protection for a poorly flown profile, only with the added benefit of being able to identify when the landing itself went excessively out of parameters.
As far as mission impact, that's debatable. Having a quarter or more of squadron aircraft down for airframe cracks is a problem. The automatic blade fold system has been a problem since the -60B, it just results in more MX hours and flight deck hassle is all.
I'm not saying different is bad, what I am saying is that we ended up with a "new" airframe that in some ways has less capability than current airframes. And this happened because of the "on the cheap" deal that Lumpy mentioned. Its taken those 10 years of operations to finally get systems onboard that provide an improvement over the -60H. Imagine how much more capable we would be now if those 10 years didn't have to be wasted.