Hi Patricia. Not sure why you are thinking you should make test cakes first? Is it because you don't know whether they will hold up being tiered?
If you have not made a wedding cake before it might be worth your time to make a test cake. And do your research on supporting it etc. That way when you get ready to do your cake you will be more comfortable doing it. When I first started I made cakes for everyone just so I could practice!
I have looked at your cake pics and you seem pretty experienced. Don't see the need to pre-make cake ahead of time. I am assuming it is try different types of flavors & icings?? :o)