Is there an actual room above in that gable?

Remove the mullions or paint them too! Read this first if you do it yourself ;)

http://www.thriftydecorchick.com/2011/06/when-diy-goes-oh-so-wrong.html 

I would also add some plant scapes at columns and use tall items. Need to break up all of that "squareness".

So nice of you to let the builder go on that. Maybe he/she will come back to show you how to remove them or at least find someone to help you. You have a gorgeous home. Really lovely.

You've probably already thought of planting a hedge as a wind break. But some wind for a lake view? Yeah, I'd take that!