Still of This World: The Aliens of Mass Effect

After calling Mass Effect and its first sequel "phenomenal", one of the editors over at Gamer Limit has voiced his dissatisfaction with the stark human-like features possessed by most of the alien races in BioWare's sci-fi series.
I found it a little strange that almost every single alien was bipedal, two-eyed, and had almost entirely human features.

Take Liara for example. She's a member of the asari race, and for all intents and purposes she is a blue skinned young woman with a weird tentacle/dreadlock hairdo. BioWare did a good job in making sure asari culture was sufficiently (alien,) but why couldn't they extend those same principles to the asari's appearance? Come on, they even had perfectly human noses with two nostrils, and teeth! Of course Liara possessed perfect, white, and human looking teeth.

Not convinced yet? Let's examine the salarians and turians. While their faces don't look (human,) both races have two eyes and visible mouths and noses. If the galaxy is as big and widely populated as the in-game universe tells me it is, then why does it seem like every (major) race evolved along similar lines? Was it too hard for BioWare to think up other organs or senses for these races? Even if Bioware deemed it was necessary for these races to possess mouths, putting them in a different spot on their bodies or faces would have helped me not feel like I was just looking at re-skinned humans.
I'd have to agree, but I don't think it's due to a lack of imagination on BioWare's part. There are most likely technical limitations involved, which may explain why the hanar play a minor role whereas the more human-like aliens are inhabiting the Normandy and accompanying Shepard on missions.