That's just how Pasolini writes books and I myself am perfectly fine with that, but I get that the end is not popular with some.

::: spoiler Tap for spoiler Galbatorix death created an unfillable power vacuum mortal non-mage Nasuada can only substitute to some degree. Eragon cannot really fight for the next 40 years or so for Nasuada - he has a duty to Saphira and all dragonkind.