Maybe we could have a paid worker who would be aware of all the marketing projects, in communication with every team, grouping all the contents/media in one place to make it easy for everyone to spread the word in a more united/homogeneous way ?
wasn't that the idea of DPOSHUB?
Correct 
Indeed, DPOSHUB will be good for coordinating our efforts so that marketing resources are reused, good ideas get promoted and workers who don't deliver get fired.
But that's not the point here. The point is who will make sure our marketing efforts are consistent and the public image of BitShares is being built according to a thought-out, long-term vision?
DPOSHUB and the referral program will not solve that. They are just incentive tools. What we need is a marketing strategy and somebody who is responsible (before the shareholders) for implementing it.
Sure, we can do without it. But then we should forget about competing with more organized entities. We will have a better product but they will have the market share.
This point (my emphasis) is surely a key challenge for any DAC, as one key difference with a flesh and blood corporation is the lack of an executive board/centralized control - though certainly this is no guarantee good leadership

One solution may be to codify an Articles of Association or constitution for BitShares that allows the election of more concentrated power with perhaps elected posts such as CTO (BM I guess) COO, Head of Marketing and - yes - a CEO. All of this could be in the codebase, though I suspect the very idea of more centralized control (trust inference) may be anathema to some of the community. Might this nevertheless be a potential solution?
Edit: url link fixed
Here is a typical list of what the Articles codify for a 'real' corporation,
sourced here.
• Responsibilities of the members;
• Directors’ powers and duties;
• Directors meetings, voting, and other delegates;
• Keep records of the directors;
• Appoint and dismiss directors;
• Issuing shares;
• The different class sections;
• Shares;
• Share transfers;
• Dividends and other distributions to its members;
• The decision of the members of Congress and participants;
• Media and communications;
• Compensation insurance for directors.