All this sounds insanely expensive. Just makes me double down on the fact that it is cheaper to make disposable satellites than make them last forever. Especially if it is cheaper to get them into space as well.
There are physical limits that forces them to have big mirrors and other expensive and relatively bulky optical elements. Also, there is no mass production due to small batch sizes (typically one or two).
So if they have a two year life span, it will not be economically viable.
If you want to go to an L2 orbit with a 10,000 Kg satellite with one of a kind sensors (relatively speaking) for earth observations, disposable doesn't make sense.
Low earth orbits with low weight satellites, pico/nano/micro/femtos - cheap disposable constellations with mass produced widgets make sense, particularly when you can launch them on another mission.