WWE are just relying on Taker/Trips to seel the PPV, and have the other shit as an undercard attraction to the big event.
Although, Punk/Orton has been booked beautifully, Rey/Cody has a lot of potential to be great, Cole/Lawler has been booked well, and Edge/ADR is slowly coming along (but needs a big boost)
I doubt WWE are even bothering to hype the Cena/Miz match because Miz is not a threat and will job to Cena rather quickly. Seeds may be planted for Cena/Rock @ Summerslam, but yeah, in an odd event, Raw won't have any top heels who could challenge for the title after ER. That's why I'm hoping Hunter turns heel post-Mania and we get one final heel Trips title reign.