A travel capsule applies the capsule method to a suitcase. Four tops and three bottoms in one palette produce twelve outfits; seven unrelated garments produce three or four.
This is why packing to a palette rather than packing outfits is the single most effective way to reduce luggage.
Rule of thumb: choose bottoms first, since they are bulkier and constrain everything else, then pick only tops that work with all of them.