Indeed the level of coolness of main event does not match level of coolness of rest of the card 
Indeed co-main event could be bigger stars.
Have you heard that UFC has signed 7.7 billion deal with Paramaunt+ ? Here is link about it https://www.ufc.com/news/dana-white-new-ufc-deal-paramount. What does it means for us? There will be no PPV anymore. If you want to watch UFC live - subscribe for Paramount+. Dont know if I want to have another subscription in addition to netflix, youtube and spotify... On the other hand its 10-15 bucks per month only.
Indeed co-main event could be bigger stars. Have you heard that UFC has signed 7.7 billion deal with Paramaunt+ ? Here is link about it https://www.ufc.com/news/dana-white-new-ufc-deal-paramount. What does it means for us? There will be no PPV anymore. If you want to watch UFC live - subscribe for Paramount+. Dont know if I want to have another subscription in addition to netflix, youtube and spotify... On the other hand its 10-15 bucks per month only.
It was an interesting move for the UFC, and it should promote fights for Americans. There should be more cards in the US. They'll basically centralize the event there; anyone who wants to take the cards from there will have to pay a lot.
I am not very certain on what you are implying. The UFC is very much centralized already with uncle Dana having the power to decide where they will hold events and also his matchmakers creating the list of fighters and who they will fight.
Also, the only importance for the fans is of this new deal with Paramount Pictures will give us a cheaper choice to watch the UFC hehehe. However, I am quite certain many fans do not care because they can stream this freely without payment hehehehehee.