Cleaning all objects before macro exit

Unless their scope means that they would remain in memory and you specifically don't want them to, it's generally a waste of time setting them to nothing in my opinion. (there are a few exceptions, such as when you have created cross-dependencies)

It only really applies if you have created your own classes and one stores a reference to another, which in turn stores a reference back to the first one. In such case, simply setting the objects to nothing will have no effect anyway unless you have implemented code to release the other object. It's a very niche case, which is why I put it as an afterthought!