A combination of both seems to me like the best option or possibly the introduction of new system at an intermediate of the two.
Steve200 read the AWB (Airworthiness Bulletin) All will be revealed. It is exactly as you said.
Perspective and Yr Right have the right perspective on maintenance I would say.
Interesting that you mention the CSU issue Perspective, that was covered in the Brazier case that Creampuff alludes to. Massive over runs, but with no apparent detriment, although he was lucky to get away with the amount of items he had on over run. Read about it here if interested.
Brazier and Civil Aviation Authority [2004] AATA 313 (26 March 2004)