If anything, I'd like a larger period for submitting ideas. For example, allowing submissions to be submitted within 6 hours of the end of the round. Maybe with a penalty for every off points gained for every hour passed or something.
Also, with combo tasks, I've found it troublesome to coordinate with the other member. Or three. That being said, I feel combo tasks shouldn't be more two members for one week. If it does exceed two members for a single task, maybe at least give a bit more leeway for the submission of the task? Perhaps one not unlike the one suggested above?