I can see where you are coming from, Phil, but Chris' comment points straight to the potential predicament if we split into two : some members will inevitably put 'common' birds into the 'rare' category and vice-versa depending on how they perceive 'common' and 'rare........we'd be back to Square One.
So, as Max indicates, we seem obliged to leave it as it is, especially as members wouldn't want to reference any new 'official' list of 'common' and 'rare' birds before we posted sightings...( and can you imagine how long it would take us to finalise such a list
....probably long enough for some of the original 'rare' birds to become 'common' and vice-versa.)Freddy