It's better not to include any cash items as they might just want to have a simple one for players. But they can add them if they think people are willing to spend more on such stuff.
The fact that there is a 55% chance that you don't get anything I think would almost make devs interested. But since you said this is Daily/Weekly/monthly I think the longer you stay on the better the chances should be
I believe this would increase mor of an active community due to people wanting to claim their prize, nice idea support