Both Presidents have done great things for the club in their own way and style. Socrates brought us out of the petrina xronia, brought us Giovanni who we all fell in love with and built us Karaiskaki and created a dynasty domestically. Marinakis did not make such big splashes signings wise, but he did modernize the club in many ways, and made our name and status grow bigger outside of Greece while making the club financially stable and healthy and raising the bar incredibly when it comes to transfer fees for our top players.
Personally I always liked Socratis' style especially with his media handling he would always stick it to our rivals but in a playful way, while Marinakis was very blunt and somewhat unbecoming I find of a prez. At the end of the day however we are truly blessed to have had them both at the helm, and we will be good for the foreseeable future under Marinakis guaranteed the man loves the club and will not tolerate seeing us at second place.
Here is a short little video on Kokkalis if anyone is interested.