Boards by category or deadline

Hello. My small marketing team has been using Monday for a month now. We realize how powerful it is, but as this is our first trust task management system, having major problems understanding the thought process no matter how much I research.

We typically use one master board for marketing tasks and one master board for our content schedule. However - our marketing task board is HUGE, and we operate very deadline driven. While this works, its a lot of little tasks - and I understand that we can filter views out. But curious if we would be better having a board per category: website, video, email campaigns - or even by department (requests, which would all be categories).

Regardless - we are very deadline driven, but really struggling overall with best practices. A lot of random marketing tasks - or a board per department/category. What is the best practice and what do you do? Does your team then just use the mywork to know what they are expected per week? How do you set priorities? Help please, very interested in how others work.