It's a nice little mark/smark wet dream if you like both companies but it wouldn't be ideal in reality. TNA isn't a big enough deal for a cross over event to be a massive deal like something like this should be. WCW was, but then there was no way those two were working together in that capacity since it would benefit the other, and the last thing either would have wanted was to help the competition. (Same reason Vince would have never wanted to accept Bischoff's challenge to him at Slamboree 1998. He wouldn't want to give WCW that kind of publicity.) TNA certainly benefits from the publicity, which is probably what Dixie has in mind, but the TNA stars don't by and large have the same kind of worldwide recognition as the WWE stars for any of the WWE/TNA match ups to really be considered "dream matches" for the casual audience.
Heyman also knows from personal experience it wouldn't work because of egos as well. Back in 1996, when Vince was paying Heyman $1,000 a week to make up for talent he took from ECW, Vince had the idea to help promote their shows and their PPV for them, and that was to bring ECW guys on the show and have a few matches between WWF guys and ECW guys. This wasn't even a huge cross over event (because regardless of the cult following ECW had, they weren't at all a huge promotion), just a few matches on Raw and even THAT caused problems as there were mid carders on both sides who had a problem jobbing even in the opening match of the card.