[Fyron]

I am not too sure how Repair works when improved, but I seem to recall it doesn't affect the actual repair rates. Is it so?

It works fine if you raise the trait. Just be aware that the trait affects the total repair in the sector, not individual components. If you have components with 1 repair, a 20% bonus would do nothing if it made each of them 1.2, as decimals are lost. Instead, it totals up all repair, then increases by 20%.