Instance variable type: array

What do you think?

It could be useful to store a set of values in the instance variable.

This

all Instance variable is the same no matter the type of Object.... array, sprite, text etc all the same Instance variable

This is supported in Containers.

You can also use instance variable to store array's UID.

Add a couple of helper functions for setting/getting values in array by its UID and voilà - you have your array in instance variable.

Having an array as a primitive variable type instead of a separate object would be nice. It would make things more readable. As is picking and functions can make it look complicated and/or make things more complicated. Don’t get me wrong, picking is pretty nifty for many things but is an awkward replacement for some logic.