The TravelPro MaxLite International 20” line may fit the bill. I hate the changes they made between the MaxLite 3 and MaxLite 5 - the new handle configuration on the sides and bottom is awful, and they cheaped out on the zippers - but it’s still one of the better options in this size class.

On the higher end, the Briggs & Riley Baseline Commuter may be an option too.