Ideal AFE

There has been some discussion about fantasy hardware lately -
especially with the cell processor.

I know the AFE on the USRP is pretty feature rich, but I still pose
this question to the group: If you could specify the AFE for a
manufacturer to make, what features would it have? Sampling rate?
12, 14 or 16-bit ADC/DAC? AGC? CIC Filters? Etc.