For most firms - of all sizes - the greatest challenge to the marketing strategy is finding a way to implement it. Great ideas are always available, the major obstacle is prioritizing them and then executing them. Those firms with marketers or consultants may rely on a professional to help with implementation, but for the majority of firms, there is no easy solution.
Nonetheless, I thought I might suggest that with every marketing initiative you add to your list, consider attaching a time line for completion. Perhaps having a date to aim for will eliminate or reduce the "procrastination factor" and help you be more efficient and effective. Be realistic regarding what you can accomplish and establish dates that make sense for your firm and the resources you have available. Otherwise you will probably find yourself simply changing the dates as they approach rather than really trying to make the deadline.
Let me know how setting a scheduled date for completion works for your marketing efforts!