the bloodlines available to you are undead, infernal, fey, elemental, draconic, destined, celestial, arcane, abyssal and abberant
don't think about whats best think about what the character you want to play would take, elves can be naturalistic and might have a connection to the fey, or the character might have attempted to go to a wizard college only to find it wasn't to there taste, these might lead to a fey or arcane background.
For reference if you want a person who might be able to mix it up the draconic and abyssal bloodlines allow your character to grow claws, not particularly strong by themselves but with the right options and spells it might be decently viable.