To add up to it.. What maintenance courses would you advice to somebody who already has a CPL to help him understand the accidents or incidents?
I'd have thought that a suitable MSc somewhere like Cranfield or Embry-Riddle would be more useful. Maintenance issues should be investigated by chartered or incorporated engineers working with licenced engineers who live and breath maintenance issues, but a CPL could back their aviation knowledge up well with a specialist MSc or even a PhD.
Althought LfaJ is quite right - no substitute for professional experience (although I'd argue that the best people have both that, and a solid academic background.)