Face the facts: Cliffy B is a punk. His engine is garbage (I'm impressed with what CCP has squeezed from it though). With the technical culture of CCP I think Crytek would be a better fit for the game and the company.

Practicality of changing from the dudebro (UNREAL BRAH!!!!!) engine:
Depth perception is garbage. Always has been in the unreal engine. Batman Arkham city will show you just how garbage it is when you enable 3d mode. I want DUST in 3d too but Crytek can do that as well as handle great depth perception without 3d mode.
Crytek also has a better texture renderer leading to longevity of the game and prettier stuff to shoot at.

Aesthetics of the dudebro engine and other preference.

CCP, again, kudos to what you have done with this garbage engine. Take the female merc's ass for example. A work of freaking art. Damn, thats a nice ass. For real.
I think Crytek could sculpt that ass too, without subjecting us to the garbage of the dudebro engine.

Also, its on principle.
Dudehuge (yes, cliffyB prefers to be called this) is such a **** (cite: xplay interview in which he tells Morgan Webb and Kevin Perrera(sp?) that there's a reason that he's making games and they are reviewing them) as well as a punk (cite the faces montage that he made at E3 when he thought he was the ****).

Crytek is licensed by the good folks over at Piranha Games who are developing the newest Mechwarrior game! And its beautiful! Albeit a little laggy but hey, their players get the satisfaction of knowing that they are not contributing to the sustenance of the dudebro.

Cliffy B might well be the Andy **** of game developers. Sure, he hasn't talked anyone back into being a ******* addict, which lead to the untimely death of well loved movie-film actors, but being a **** is still being a **** and discouraging that behavior where you can is a noble endeavor for sure.

Or create your own engine, like you did with Carbon Based, which is a technical marvel.

Best intentions,

Cassandra