@eddiespino thank you for your comment and encouragement!
If I may ask you also used only rented cards? On how many Summoners did you focus?
It seems to me that playing with only one is not very optimal. I'm easy to counter, I have little chance to get rewards in Daily Focus, and I don't learn much about the meta.
I wonder if I should spend more time on "cheap" Bronze to learn how 2-3 decks perform, instead of trying to climb to Silver to soon. I would really appreciate your opinion on this.