Just a commentary, but I find the process of getting permanent perks to be unsatisfying. Getting to them often requires me to completely tailor my perk selection towards them, grab several suboptimal perks, and then sit idle for a long time in order to earn the 5 or 10 points required to buy the perk. All the while I'm thinking "maybe I should use this point to buy <so-and-so perk>, that'll make things faster... Oh, but level requirements are always 2x the previous level, and this perk won't make things 2x faster, so it is actually slower to spend the point than it is to just be patient... Or maybe I should rebirth now for the extra multiplier and just start over..."
After I actually get the perk, I don't take time to appreciate it, and instead I want to immediately rebirth because now I start with essentially an extra +5 or +10 perk points for free, plus all of the points I don't have to spend on the useless perks, so I can now spend those all on perks that help me actually advance.