> vacuum in the market for an "everything store" that's actually good.
I would like a "what store is everything in" product. Search for something, and it gives you back matching products in stores 5/10/50 miles from you; purchase online, pickup from the store (or pay for an ubereats like delivery). As you build a cart, it attempts to cluster items. You get the convenience of search and online purchase, so that you don't waste time wandering around stores and not finding things, and you get the item in your hand quicker if you're prepared to go get it once purchased.
Big advantage to whoever built it: you don't need to compete with Amazon on logistics. On the other hand, you have a hell of a network effect to overcome, though if you focused on one geography only to start, it could be doable.
Such a thing, if it took off, could reinvigorate physical retail businesses. Google had a half-assed attempt for a while with local shopping, but they never really pushed it that hard...which I think was a missed opportunity.