It’s a reasonable idea, but implementing would require creating a parallel grind because creating time-sinks is one of the main goals for a game like this. Grinding better aspects is one of the things that makes replayability.
The other problem is that if you reroll a Lvl1 character and those aspects in the Codex are all level 90 power level, you steamroll content. This could be have various levels but then advancement becomes level gated which is boring.