My Crayonista idea for the 185s, as a relatively small non-standard fleet which can't run in multiple with anything else is to move them somewhere with exactly that as a requirement - Southern, freeing up all the 171s to have their couplers changed so they can go up north where the ability to run with sprinters might be useful.
171s only have dellner couplings so 377s can drag them in an emergency and vice versa, I don't know if it's ever happened but if it's a consideration either refit the 185s with dellners or have a "thunderbird" loco at Selhurst depot or something.
Perhaps if there are enough of them they can go to SWR too, replacing the 159s.
Disgusted of Tunbr... err Uckfield would complain about the 10 car peak 171s going to 9 car, but they could provide a better overall service - 3 car permanently on Hastings - Ashford instead of 2, and 3/6 cars as the minimum off-peak length on the Uckfield line rather than the current 2/4