I think the 320 would be a good option if it had significantly more MPG. You lose a lot of performance over the 328 and you gain really nothing in MPG. I like the simplicity of the options, but to me its not really a good value at all. Especially on lease I cant imagine it being that much cheaper then a 328 once you put some options on it.
Kind of reminds me of the old 318's that were here, poor performance and not a huge increase in MPG.
I guess you could tune it for more performance, 0-60 in 7.1 isn't exactly slow but not not very fast either. Its about average, but will get blown away by any Accord or Camry with a 6 in it these days, its on par with a 2001 325.