one of the things i've always liked about the sorcerer is their self-sufficiency. since they don't need a spellbook and get eschew materials for free, they can never be denied their magic.
except that all bloodlines except celestial and infernal have at least one bonus bloodline spell that requires a focus or expensive material component.
doesn't this defeat the purpose of giving them eschew materials?
How do you know what the "purpose of giving them eschew materials" is?
Also, there're definitely more bloodlines without spells with any non-covered material/foci.
Just because some bloodlines have a few spells that require an expensive material component does not invalidate eschew materials. It still covers the vast majority of the sorcerers' spells. Doing a quick look over the bloodlines it seems like it is usually the highest-level spells that are not covered. Most of those spells tend to be those that are easily abused. Wish in particular could cause problems if a player can cast multiple wishes per day with no cost or consequence.