I know this sounds awful, and like a terrible calque of the French, such as a beginner might produce, but let me assure you all the terms I used are approved Eurospeak. If I could have ticked "English (EU)", I would have. Trust me, I did a big project about retirement schemes in the EU a while ago. You could perhaps use "scheme" for "regime", but otherwise I'd leave it as is.

Actually, "by capitalisation" occurs in the reference document as well, but it makes it sound even worse. The document uses both "by capitalisation" and "capitalised"; so I think you can take your pick. It also uses the word "complementary" to describe a regime.... Every terminological choice made above is vouched for in the document somewhere.

c'est un peu lourd mais tout y est