"As to whether having a child-shaped doll that you beat up and/or have violent sex with is 'wrong', well, I don't think it's any more wrong than playing a computer game that involves shooting people, or writing stories about how you'd like to dismember your co-workers."
Yes quite.
I don't think many people apart from you have actually said this sgb.
Clearly if the argument is that it's fantasy and no harm done, then anything goes in terms of what the robot looks like and what behaviours it displays.
My point is that if people feel discomfort with fantasies that would be distasteful, harmful or criminal when carried out in real life, they need to ask themselves honestly why that is. Because logically, they shouldn't. Like you don't.
TBH as I've been saying I don't think these would result in an increase in sexual violence ect (although I don't know obviously) but I do have a very instant visceral reaction against the idea, which I have been trying to explore but not had too many takers in actual engagement 
I'd be with you though, if we think that these are no problems, then they should meet whatever the market demands in terms of look / behaviour.