So, I'm just thinking, as far as I'm concerned, you need to start all over from scratch, a new character and all, to sort of gain the best outcome from patch 1.9 right?

Well I am, of course not, going to do that, since I am very far in the game.. So my actual question is, what should I do with my game when the patch arrives, that does not include starting over?

I really want to get the strongest impact on my game from the patch!! So, some advice on this would be much appreciated!

You can install everything from the beginning but keep your saves files and see if that works out for you.
The next step is to delete everyhting and start over again, it's up to you a thing !!!