Ask PG : is company culture a priority from day one

9 months into my startup project, I've been working on and off with quite a few (expert accountant, famous author, cartoonist, developer and web designer), all volunteers. I feel now I'd better wait and find a really fitting match for me (=different skills, tech, but personality match) and for the project (=living a life coherent with the content/positive parenting). How much of a priority is it?