Bike hooks I think are worth it, one per wheel. One thing I do is bag them in translucent polybags. Keeps the dust at bay and slows down oxidation.
One thing I used to do and do no more is store wheels with tires in wheel covers as seen often in the 70's most save for the two types of Clement wheel covers are PVC coated...
PVC volatiles are bad for tires long term. A note from experience.