It would be really nice if there was support for setting non-string data types as custom properties. I've been able to make due with this limitation by using toInteger() on all numbers and object mapping to go from JSON to objects and vice-versa, but it would be amazing if I could cut out this extra code and just set an object or integer directly as a custom property.
My QA team imports our application's compiled JARs into ReadyAPI and maps JSON to objects so we can easily just use the classes getter and setter methods. To pass these objects (and other data structures like maps, lists, and arrays) around our test scripts, we've continually got to stringify them to be able to set them as custom properties, then use an object mapper to map them back to objects.