This is truly a great idea and love it when I see casinos tryibg to get their users(customers) involved in their decision making process because to me it shows that the casino has some degree of respect for their users.
That's one reason why a casino is being enjoyed by its users because of their involvement when they ask questions like surveys on what their users think is best for them.
Even in the simplest type of weekly or monthly bonus, that will sustain the happiness of many gamblers. Despite the losses, when they're appreciated like that and even a few bucks of bonus will make each of us happy.