Thanks for asking about this.  The intent isn't to stop the use of the 'easy' keyword, but to try to reserve some tickets for May.  If they are just marked as 'easy', then there could be more of a risk that someone would work on it before the sprints.  By assigning them to Mariatta, it will serve the dual purpose of trying to reserve these as well as making them easier to find later on.  I think the equivalent would be the ability to add an additional tag to GitHub issues, such as when there's a 'good first date', 'help wanted' and 'sprint' tag on the same ticket.

But, I also don't want to complicate the current process, so I apologize if my idea isn't constructive.