Both those suggestions seem a bit hard on the regular users that aren't turning to churning.
I'm wondering if Dooyoo set aside a pot of money to fund this drive for new members, and when it's finished we'll find a new 1 review per day limit slapped on the rules. Or something similar that fits with their budget. It would be a good solution IMO.
EDIT: Who wants to write a review about Dooyoo's new payment system? I've just stumbled on the title for you - Turning to Churning.