Kittonwy, the sad thing is, R2 had gameplay that was condusive to stop and pop mechanics, and individuals like you ruined that during the private beta.
People wanted the accuracy differences when moving, stopped, and in cross hairs gone (which all together brought down the effectiveness of stop and pop). The wanted the game sped up, which further destroyed the ability to use stop and pop gameplay. They wanted no fall damage, more run and gun. They wanted grenades to have the Brett Farve effect again, tossing across half the screen.
Basically, all of the elements that were changed from the private beta (as requested by individuals like yourself) are what made the game what it is today. So you (and people like you) made your bed, now sleep in it.
Insomniac knew what they were doing in the private beta, and it was changed to cater to YOU, blame them, not Insomniac.
R2 maps were never conducive to stop-and-pop, want to see stop-and-pop maps? Check out SOCOM, Killzone 2, Call of Duty 4, where corridors are more narrow, corners and rooms are generally more confined.
If you're doing stop-and-pop, regular moving speed would have to be slow, running speed just a tad quicker than what we have now, zoomed-turning would be slow, cross-hair doesn't need to be gone, but the weapon damage has to be upped. Right now the weapon damage isn't high enough for stop-and-pop. Also the problem is the way the maps are designed which are more often than not open rather than confined, which also take away from the stop and pop, as such, stop and pop doesn't work well in the maps but hip-shooting doesn't work either, making run-and-gun much less effective and very range-limited, resulting in a MP experience that is neither here nor there. The controls/aiming/weapon-tuning is not consistent with the map design.
Other than the grenades, very little was changed from the beta, Insomniac didn't listen for the most part to the beta-testers, the majority of which were not satisfied with the gameplay (in a thread where a poll was taken more than half of the people preferred R1 over the beta which should NEVER happen), the build we got was merely dismissed as an old build, to this day there are people on myres (myself not included) who are still dissatisfied with how the game plays, enough of them that they have a 15 page thread dedicated to just complaints.
I know you went to Insomniac and somehow feels they're now your friends but I've never been in a beta that was supposed to go smoothly to build hype where there was so much backlash.
To fix things without touching the maps one would have to change the way the reticle works for medium range weapons such as the carbine and the bullseye, making hip-shooting effective again at medium range and it would be a significant change that they would be unwilling to make. Right now I doubt it's enough to just tweak things and somehow the game would feel right.
Insomniac made the game, they're the ones who are in charge of balancing the gameplay, ultimately they are responsible for how well or not R2 plays. Personally I want the gameplay fixed so I can put my copy of R2 in and enjoy some MP competitive, and convince some of my clan mates to actually join in, because right now most of them don't want to.