Is cross promotions good for MMA?

With Conor Mcgregor vs Floyd Mayweather being the pay per view of all time and Ronda Rousey making her second appearance into WWE, do fighters fit well in anything other than MMA or when celebrities and athletes get into the cage does it help bring a new audience to the sport? Ever since Brock Lesnar stepped foot into the octagon, he has been a marketing machine. Whether in the cage or in the squarerd circled the guy is a beast and people just manage to gravitate to him. The former UFC Heavyweight Champion and current WWE Universal Champion laid down the blueprint for professional wrestlers that want to become top level MMA fighters. Since Brock Lesnar, we seen the likes of former WWE Champions like Dave Bautista and Bobby Lashley has had a few fights in the cage. Rumors circulating that Ronda Rousey maybe making her in-ring debut soon and former WWE Superstar Ryback maybe getting ready for his Mixed Martial Arts debut late next year. With the success of Mixed Martial Arts through the UFC, pop culture has easily picked up on it to the point it has become a household name. Chuck Liddell helped innovate the sport throughout its earlier years because of his mohawk and wildly fighting style. Chuck would participate in movies, tv shows, and even magazines. This success would help generate an audience and make a lot of noise. Celebrities came left from right and outlets had good and bad things to say about the sport. While Chuck and rival Tito Ortiz were helping build up MMA in the United States, Japan had Pride fighting Championship. Pride brought anybody and everybody from the most vicious fighters on the planet to guys like Bob Sapp, Emmanuel Yarborough, and even Giant Sila. Respected stars from different sports with fighting backgrounds what so ever but helped bring a new audience together. It wasn't until early 2007 that Mixed Martial Arts would reach a whole new wave of success off of backyard slugger with a whole mainstream of success. That mans name is Kimbo Slice and he had shows packed to see him and ratings skyrocketed once he touched tv screens. He look was unique and he had great punching power as well. Kimbo was the perfect star as far an fighter should look. MMA analyst and longtime fighters didn't like the success of Kimbo due to his rise to fame and no background in MMA what's so ever. They couldn't understand it and deemed it as unfair but the fans wanted more from him. He would get his first loss in 14 seconds to Seth Petruzelli and Elite XC would crumble after. Longtime former WWE Champion CM Punk would make his debut with the UFC against Mickey Gall and would be submitted in the first round. Punk whose real name is Adam Brooks would train for a year at Duke Roufus gym alongside Anthony Pettis and Current UFC Welterweight Champion Tyron Woodley. Great training camp and great team for Punk but I would've liked to see him fight in a lower league to get his record and his skills up. Maybe a league connected with the UFC and put him on Fight Pass Maybe and get subscriptions up. Whether the UFC decides to do that or keep him on the Main roster it's a win for them. Though it isn't the first time this has happened but not only does cross promotion help build numbers but make bigger stars to the audience. After his performance with Floyd Mayweather, Conor Mcgregor should really negotiate his contract with the UFC. Cross promotion definitely helps bring in a new audience and with the right skills maybe new stars of the sport. Should it be done more or will it hurt the respected sport in the future. Give me your thoughts on what should be done?