If Bioware gave the option to customize Hawke before you meet him then same could have been applied to our Warden. It doesn't matter if they had many voice variations in DA:O, they could have simply gave in two versions of male and female like they did to the Inquisitor.
We considered it.
In the end, there were simply too many variables, too many issues with implementation that would have made the net worth of physically including the Warden problematic for the very people that said inclusion would ostensibly have been for, and, ultimately, we didn't want to.