Gnd, completely agree that Pu, Wc and Gz are all dead options longer term. The golden ticket right now would possibly be an aircraft with the size and disposable payload of the latest Blackhawk but a cabin more akin to the Puma and stability/ride comfort of a Merlin. But I don't think that exists now. Nothing out there right now will get us a step-change in performance/capability but everything we have will or could be extended until 2030+ when there are likely to be options that revolutionise the medium lift role.
It's not an easy sell to put up with mediocre medium lift BH in the interim, but we quite frankly don't have the cash to buy and train a force to operate Blackhawks/NH90/AW139 etc as a nice way to tide us over until the next tech comes along. I therefore suspect that what we have now will be with us for a long time just yet...