Lay everything out
Group items by task: power, food and drink, repair, light, and cleanup. Photograph the layout. Mark anything used on the last trip or project; put uncertain items in a separate row. The point is to see duplication, not to make the kit photogenic.
Run a small scenario
Choose one real task you expect next weekend. Can you complete the first five minutes using only what is in the kit? Note the missing item, then ask whether something you own elsewhere solves it. A product belongs on the list only after this step reveals a gap.
Set a purchase rule
Write the job, size limit, and maximum spend before browsing. Compare the candidate against a no-purchase fix and one alternative. Keep the list for a week if the need is not urgent. The guides on this site use that same rule: practical problem first, product second.