Random thoughts for the day while I wait on some of my servers to reboot...
I think Liara would have been much improved if she'd been a little bit more like the badass shadow broker back in ME1 - the fainting part just drove me crazy. Was replaying ME1 the other day, I wanted Wrex to jump up and say STOP WHINING!
But given that her character got a lot more dark in 2 and 3 I think she improved over the trilogy. From what I hear of Ashley, she never regained the depth she had in ME1 but I wouldn't know for sure. I think Garrus had a brilliant story throughout the series (and goodness I loved his Homeworlds story), and I love how Tali realized at the end the truth about the Geth and Quarian history...
Of course, Kaidan's story is splendid and I love how he matured (dat grey hair...

, but I really want to know more about the missing time when Shep was busy fighting collectors, and about his biotic squad.