I imagine they're going with Mii-like avatars because they have business contexts in mind. What they could do instead is to give people at least two avatars for different contexts and then let the tool/environment set which they're using.

e.g., if you're in a business meeting, it automatically runs with your Mii-like avatar, otherwise if you're roaming a desertscape to relax on the couch after dinner, you can be a pink lemur in a cape and cowboy hat. Might as well prep for both contexts now rather than putting off either potential customer.