If your UX designers can stomach it, simply ensuring async actions have a defined signpost to signify completion is the most helpful. E.g. an element that shows

If your UX designers can stomach it, simply ensuring async actions have a defined signpost to signify completion is the most helpful. E.g. an element that shows up when results are finished loading on the page. "Spinner that disappears" isn't terrible, but isn't great either. "Everything looks the same, and then some results load, and more results might load at some point, maybe" is sadly not that rare.