This is not an exhaustive list, but I generally think there are 4 distinct categories you might want to consider when identifying topics for your marketing videos.
videos about a hobby you have (for me, it's boating and fishing)
videos about yourself or your family (I'll be making videos of our upcoming camping trip)
Videos about your profession or occupation (I make some general videos about the law)
Videos about your niche (I make videos focused on farm and truck accidents)