In my imagination, Murderbot looked kinda like the player character from the game ‘Citizen Sleeper’, pictured below.
Which is to say, very androgynous and very obviously cybernetic.
There’s quite a bit of character similarity between them too, because the titular Sleeper is a human consciousness in a cybernetic body that has a lot of biological parts, and they are kept loyal to the company who owns them by a drug that will cause their body to break down if they stop taking it. Same intent as the governor module, but a different approach.
I found Murderbot’s physical appearance an important aspect of the books, not just for surface plot reasons (everyone knows they are a bot etc) but because it’s a large part of what people need to overcome from the perspective of seeing past their prejudices.
Yeah, I agree the bots are genuinely "more fleshy"and with skin and such - just saying where my imagination was at - which thanks to the wonder of books can be quite different for different people.
I wish we knew what the motivation was for choosing the actor. The cynic in me thinks they opted obviously male lead to reduce friction and claims of “wokeness” but without some inside insight we can’t know.