Please, don't suggest fully upped and shard decks for bronze and silver farm...
Why?
Probably because almost everyone interested in farming the lower leagues is rather new/poor and doesn't have access to so many upgraded cards.
And everyone who played long enough to be able to upgrade at least 30 cards shouldn't have a problem with farming bronze with a deck of his own.
I think veterans sometimes play bronze/silver; I know I do. Yes, I do use a deck of my own but I'm still interested in learning what others use.
Given the paltry number of decks recommended in this thread, we should all be focused on getting ideas in rather than keeping them out.
Everyone seems to agree that unupgraded Bronze/Silver grinders are an "important" category, yet we only have two submissions so far... and one is a deck that clearly belongs in the PvP thread.