What makes a creative brief good?
A good creative brief is short, specific, and brutally edited. It should fit on 1.5 pages or less. If it runs longer than that, it means the strategy hasn't been resolved yet and the brief is compensating with volume.
The most important quality is the Single Minded Idea. If that section contains an "and" or an "or", it's not single-minded. A creative team reading it will pull in two directions and you'll end up with work that doesn't land.
Mandatories must actually be mandatory. The more "must-haves" you add to a brief that aren't genuinely mandatory, the more you box creatives into producing safe, forgettable work. If it's not a hard requirement, take it out.