#2 (Will) They both know their stuff
Obviously, both men know the wrestling business pretty well. Paul Heyman is very much in touch with how it has evolved over the years, as seen in his brief but encouraging interactions with talent in some of WWE's backstage documentaries. Eric Bischoff is more in tune with the entertainment aspect of things. This would provide both Raw and Smackdown with a distinct feel and presentation. Both Heyman and Bischoff know what needs to be done at the onset to make progress on each show.
Eric Bischoff spoke about how the brand split was doomed to fail if Raw and Smackdown did not feel different enough, during a live spoken-words show with Inside The Ropes. Paul Heyman, also during an Inside The Ropes live show, spoke about the time he came out to CM Punk's music in Chicago and basically prevented Monday Night Raw to be hijacked by the rowdy fans.
Both men know their stuff and will surely bring a lot of wisdom to the (creative) table.