Would you be down to see an event like this again?
Boxing vs Wrestling
Karate vs Aikido
Jujitsu vs Judo
Wing Chun vs Jeet Kune Do
You could have it broken up into three categories like Men's, Women's and Senior's where the latter category would be like a specialty bout like Dolph Lundgren against Steven Seagal or Jean-Claude Van Damme against Benny Urquidez.
It would be very traditional, not looking like a cage fight. It would be done basically on open ground on a padded floor (let's say 90x40 similar to a basketball court) where the combatants meet in the center of the arena floor and anytime they were knocked down or taken down the action stops, and they have to restart. Whoever scored the throw, takedown, or knockdown would be awarded a point.
This would continue until one either submitted, quit, got knocked out or injury prevented further action. Of course what I'm describing would be for the senior bouts, showing them as much respect as possible to get as many opportunities as possible.
The standard men and women's bouts would be treated like MMA bouts except when the referee called for a break in the action they would have to get themselves in a specific fighting position (ie, standing right in front of each other) to restart the action.
I'm not entirely convinced that the first few UFC events truly answered the question as to the best singular discipline considering how the events were basically put in the Gracie's favor. It quickly went from an event in theory to determine what was the best discipline into an advertisement for jujitsu.
Something like this needs to be put on again to really give singular disciplines the chance to really demonstrate what they can do and what is truly practical and what isn't.