The book Disneywar is really a fantastic read. It, in my opinion, paints a full picture of who Eisner was. He was responsible for saving the company. Had he not been successful, then Comcast would probably own the Disney company now and very few of us would be interested anymore.
Eisner was considered by many to be as creative as Walt when it came to movies as he had been very successful in everything that he had done. When paired with Frank Wells and to some extent Katzenberg, he really was a fantastic leader. The parks were revitalized under him as was Disney animation. It was under his leadership that we saw The Lion King, The little Mermaid, etc... and Disney animation leap back to the top. We also received MGM Studios, and he threw a ton of money at making Disneyland Paris the most beautiful theme park possible at that point.
Unfortunately a number of things happened to derail him on the second half of his career. Euro Disney failed causing him to re-evaluate the money spent on theme parks, Frank Wells died in a helicopter crash, he had a major falling out with Katzenberg (who was his animation creative lead). Along with those major losses, he also began to have a major ego issue as he felt he was the second coming of Walt Disney and that it was he alone who had caused all the great successes for the company.
Without Wells to guide his business moves as Roy did Walts, without Katzenberg to help lead animation, with his ego problems and the failure of Euro-Disney, with his heart attack, things started to go downhill. He became paranoid in many ways and cloistered himself as the sole decision maker at Disney.
It was at this point that Roy Disney Jr, the man responsible for bringing Eisner to Disney, decided to step in and begin a campaign to remove him as he really was becoming a disaster. The parks were not getting any attention to them and were in a sad shape of repair, he had killed the relationship with Pixar, Disney animation was losing respect, etc.... So the company turned to Iger who started out by successfully purchasing Pixar and bringing Lasseter into Disney creative as well as Pixar. Money was allocated to rebuild the Disney brand in the parks, and a focus was once again put on bringing Disney animation back to the forefront.
Things haven't moved as fast or as often in the right direction as many of us would have liked, but he is a better leader than Eisner was towards the end. Unfortunately, I don't think he'll ever be as strong a leader with as many successes as Eisner was at the beginning, but the company is headed in the right direction again.
My main focus is on the parks, so I do hope that Staggs is far better than Rasulo (who was awful) will be. Rasulo hated the parks, he never wanted to be in them, he killed each parks brand and moved to the generic Disney Parks branding. I'm hoping that Staggs will see the sense in moving away from that, back into rebuilding the individuality of each park instead of making business decisions solely upon the profit that could be wrung out of them. However, as others have stated, it is far too early to tell how Staggs will be as the new head of the Disney parks.
My dream would be to eventually have Lassetter paired up with some strong business mind. It seems it is situations like those in which the company fairs best. A creative dreamer paired with a business man who understands the importance of the dream. Walt and Roy, Eisner and Wells, Lassetter and ?. One can dream.