You're right, the main reason for the trend towards speakers being moved out into the listening space is to help increase that "airy" feeling and imaging detail. There have been a few speakers that did a really good job in that area even pushed up against the wall, but they are the exceptions, not the rule.
As mentioned, the Allisons Ones were quite good, having been specifically designed to be placed ONLY up against the back wall and they have a similar tonal balance to your 2Cs. You'd loose a little in top end detail I suspect, but not so much as to be disappointing IMO - Allison Twos are just smaller versions of the same design, so the sound is almost identical, only they give up a few Hz at the bottom. If you have two good corners and can find them, Allison Threes are half of the Ones, designed to be put all the way in the corner, so VERY unobtrusive!
If you can find a pair of Snell As, they too would sound familiar to you, with a lovely full bodied sound and excellent driver integration, but you'll loose a bit of stage depth IME. Bass is similar to the 2Cs, but perhaps not going quite as low... I never found my As wanting in bass depth, but I'm not a real bass freak either.