We're going through this with my son right now as he prepared essays for school. His grammar is what you would expect of a 5th grader, and while we're far from helicopter parents, we also are tempted to spruce up the paragraphs to make them look more polished and professional.
The same challenge is happening with your marketing as well. You *may* have a better way of writing, or of editing, or of positioning (and--side note--make sure it's really better and not just *different*)! But you also need your people to learn, and hopefully you're on a team and culture that allows for that improvement to occur. If so, find ways to let it ride.
There's no substitute for gaining confidence; your team will feel great when you do interject (instead of feeling like they should just always defer to you and your judgment) and you'll gain the reputation of a leader who trusts their people--an awesome badge of honor to wear!