I don't think we have a feature request for this yet. Do you mind double-checking at bugs.freenas.org to verify and to create an issue if one doesn't exist yet?
I just completed replacing drives on a vdev in 11.2 and it auto-expanded shortly after the last drive was resilvered. What setting are you having to change?
I think it's a matter of expanding the pool view--to show the datasets as soon as you click on the pool page, rather than having to click the arrow to expand the list. And I agree that would be nice.