One of my regular groups played through the first 4 books of the Legacy of Fire AP until the GM had to hit pause because of her other commitments. In that campaign, I played an oracle who was very much designed to be a support character, healing and buffing her allies, and acting as the face of the party. She did very little else in combat except making knowledge checks and occasionally providing flanking, and never owned a magic weapon because it would have been wasted on her. She finished earning the Healer's Touch achievement feat just before some effective battle magic (like holy word and flame strike) finally came on line, when dealing damage would no longer penalize her progress.
Our GM allowed me to take Leadership, and my cohort was an element-patron witch, one of the many prisoners we rescued during the campaign. That gave me a way to contribute to offense, providing some area-affect attacks and utility spells, which made up some for the loss of the party's other spellcaster when one player dropped after the first or second book. (To simplify tracking spells for 2 characters, I gave the cohort an archetype that made her a spontaneous caster as well. That worked pretty well in practice.)
My character had an almost symbiotic relationship with the party barbarian, who was aiming for the "survived a ton of damage over my career" achievement feat. He grumbled good-naturedly about how the healing he received slowing his own progress, but he also appreciated not achieving the "oops, I died twice" feat first. His PC was critical to our party's success, because roughly half our damage output came from his oversized weapon. So I certainly wasn't hurting the party by focusing solely on defense most of my career, and keeping them all in the fight.