If you make a custom property, say a string/number/float, it would have an options tab in the property create menu. You can override the options but it would give you a list that you could choose from.
#Options to custom properties.
hollow kindle
vernal crater
Options as in a custom property that could be a string, number OR float?
I once suggested (but not in here) having a 'lua table' as a custom property type - we have data tables but the idea is its a bit like player storage or player private network data - if the custom property is networked it would serialize the lua table into its binary pbt form