Your primary category is the single highest-leverage field in local SEO. "SEO company" and "marketing agency" are different queries with different competitors. Pick the one that matches what you want to be called for, then add the rest as secondary. Changing your primary category can move rankings within days — in both directions, so change it deliberately and note the date.
Then fill the fields nobody fills: the services list with individual descriptions, the business description with the terms you actually want to rank for, opening date, attributes, and the Q&A section, where you can post and answer your own questions. Photos matter too, and consistency beats a single bulk upload — a few new ones each month reads as an active business.