The best analyst briefing decks that I've either seen or helped build are not filled with marketing messaging. They clearly layout what analysts typically care about, which could include the following: trends you've observed in market you operate in, the challenges your product(s) solves, overview of your growth trajectory, industries you touch plus key use cases for each, unique differentiators, and insight into the product & (high level) GTM strategy and company vision.
Other elements I'd suggest: Include customer success stories, lay out the ecosystem that supports your products (ie. partners, integrations, develop engagement), and share how you support your customers. Also, it may seem obvious, but I'd caution against including stats/proof points that were produced by another analyst firm. In general, have a clear agenda that includes space for Q&A and listening to their feedback.