In my opinion, a European Union elected president is not required for strong management of the EU. Because it would lead, in my opinion, to power grabbing and corruption in an organizational union that needs to operate in a transparent and open forum. By electing an individual member as president it diminishes the equality that the union was formed to promote.
No, an elected EU president and strong management of the EU is not required. Each nation-state in the EU has been without war with one another for over a generation now, bordering on two generations. Each unique EU state also has hundreds, if not thousands of years of individual culture that might be drowned out if a strong figurehead emerged.