Had the same concerns about Roc Nation myself after watching that American card on Saturday night. Rigo was absolutely terrible, he didn't even seem interested, very strange.
Think Ward Kovalev will be a great watch but like you said, Ward has never been a big draw.
It's sad to see boxing how it is with the politics of the different promoters, advisors and sanctioning bodies. The WBA are taking the p*ss with their belts as well, they can have up to 4 world champions at once technically (with a super, regular, interim and champion in recess I believe). None of them are going anywhere so it's only going to get worse over time which is really sad for the sport.