@ TaLaR: Restoration costs vary by number of (D) mods. If it is only one, your are right. However, ships I recover have at least two (D) mods, often more. Restoring heavily damaged ships can be very expensive.
Pather Lashers are nice, but I usually outgrow Lashers by the time I grab one. Same thing with pirate Mule. Pirate Mule is classic Starfarer Mule plus shielded holds, which is good for a hybrid, but by the time I can afford to restore it, it is obsolete. Mudskipper 2 is fun restored. It is a better Brawler, with better weapon and mobility system. However, I do not need it when I can restore it.
I do restore ships I plan to pilot or absolutely need peak stats. As for Tempest, it is relatively rare, but it functions just fine heavily damaged, and I often leave it heavily damaged to exploit the deployment discount. Its main power is the Terminator drone, which does not care about ship stats. Also, the main use of Tempest in my fleet is to enable auto-resolve, and if that Tempest is the only one in my fleet, I rarely deploy it except for auto-resolving. If I have two Tempest, I might deploy the pair to take out annoying Lumen and Glimmer duos and the like.