Either keeping chores stationary for a semester, or rotating a subset of chores, might make most sense. This can people to opt out of cooking, say, by doing more cleaning, or vice-versa. Having stated labor goals often helps when putting together a suitable labor system. Some systems work on a time basis or a job-desirability basis, where chores are rated on these scores, and allocated so that everyone has a roughly equal set of tasks. Apprenticeship systems help smooth out transitions to new jobs, particularly the more technical ones, as do written guides which suggests what exactly should be done as part of each job.
Penalties are a potentially large issue.
These should not be punitive, but should instead be behavior-changing. Monetary fees or extra chores are possible punishments. This is a position in which an apprenticeship system is very helpful. It's helpful to keep a record of good contractors for various different kinds of work. Hiring members as workers is also a good option.