It certainly would've increased the workload significantly if they aimed to strike the same form of connection between the gamer and the characters by having a 4th. Though, I imagine it could be done if the character is worth the extra work.

I'm thankful for what we received, and I do hope that the team behind it has enough creative ideas to push for a sequel. There's a lot they can work with. So many interesting little tid bits within the magazines.

That would have been interesting a human character that hates androids would have been a nice perspective too but that was essentially Hank so it worked out.