With its small financial purse, the Canadian air force is choosing the first option, i.e. do the minimum necessary to maintain its current operations. ADF is expected to slowly disappear over time. VOR will disappear a little more slowly. INS systems will always be on aircraft. Of course, making ADF or VOR an option rather than a required system takes work also.
Regulations have to change, and aircraft systems are affected beyond just sensors and displays.
In the mean time, we better buy smart, if we still want to operate tomorrow.