Sounds like a good feature idea to me.
In the meantime you could try this:
Give the objects you want to pick from a new private variable.
Use a for each loop to assign a random number to that variable for each object.
Pick the object with the highest value for that variable.
This has the advantage that you can use it to pick all the objects in a random sequence without repetition. Just do the above. Then set that object's "random" variable to -1 and next time you pick the object whose variable has the highest value it will be a different, but still random object. Once they all have -1 for that variable value they've all been picked and you can start over.
Hope that was clear. Let me know if otherwise.