I totally understand your frustration. Gold and even higher silver ranks are out of reach without spending big $$$. However, Bronze I and Silver III are attainable. I have only been renting about 30 DEC worth of cards daily to hit my daily quest and my rating is high enough for Silver III.
At least that way I can get a decent season end reward and hope for something Golden so I don't have to rent as much next time :)
Happy hunting.