I like shops with friendly staff that are willing and available to help without hovering over you. Bolts of fabric shouldn't be standing on the floor even if the floor isn't dirty, find something that lifts it up even an inch or two. And don't over crowd the shelves so we can't find what we are looking for. A store with space to move around without constantly bumping into another customer. Convenient hours, when will retailers (not just quilts shops) understand that many of their customers work for a living and are actually at work the same time the shop is open? I've noticed a lot only offer classes during weekdays and while that may be convenient for some customers it doesn't work for all.
And most important of all, really good lighting. I drive an hour to a quilt shop because it meets all these criteria but especially because Quilt-a-way has the best lighting I've ever seen in an LQS