Strategy _ similar to business strategy, marketing plan will capture strategies required to support your business strategy. For example if your business goal is to achieve 20% increase in sales, your marketing strategy would be to 1) introduce new product, 2) increase price for premium offerings, 3) recruit more distributors and offer commission scheme and so on. Strategy is king. When you can see your business in totality, I can assure you that you will find it easier to manoeuvre. Marketing plan is the place to address all these issues.
I once sat in a meeting of project and business updates and suddenly one of the directors said, actually with all that we have now we can be in the medical device market. Violaaa!!! This medical device company used to service government hospitals and they have all the equipments. It's just that they never thought of going direct to the hospitals and take the lion share of the business. In that meeting, after going through the company yearly updates, this "innovation" came instantaneously and the next year they are pitching about it to the government hospitals directly.