I have both (mono speedy and D ring hobo). They are both in the signature collection, but I think the speedy is a must have bag. Get that first and then the D ring.
I think Gucci with white trim is cute but not sure roll handle would be comfortable on shoulder. Having Gucci will be a nice change but I think Azur Speedy is easier to keep clean comparing to fabric on Gucci. Am I helping here? LOL
I was like you choosing between Gucci / LV. They are right Gucci always on sale and you can always get the same bag cheaper later. I heard some will go as low as 50%.