The death of DCS has been greatly exaggerated. There are many, including myself who will continue to use this system. The responses by members here are their opinions, including myself. Since you indicated you have MTH Proto-2 engines, I recommend you stick with DCS. Remember all Lionel engines can be run with DCS but DCS can’t be run on any of the Lionel systems other than a straight transformer. Even if DCS does disappear I am confident my 5 yr old system will outlive me.
Why would anyone starting a new layout without any current command system, want to acquire a DCS system now without knowing what the future of the system will be?
Considering that parts may no longer be available to repair these systems and the current online prices that are in the $500.00 range.
Certainly if you already have the system, continue to use it till its dead, but I wouldn't invest in something that may soon be obsolete.