Apologies for being quite a bit late. it is most likely a feature, considering some are meant to be lovers... hence the purpose of the lover module.

Some of them have droid mentality though. It sucks that a Vanometric cell android still needs rest, despite the description saying that they don't need energy and food anymore

I personally dont mind this. The Van Cell saves on having to feed them food or charge at a station/conduit (amazing on long trips!). The worker androids dont need sleep for me, but the more life like, the more mimic'ed to human. Not saying Coconut is wrong, certainly, but just offering that the current option is my preference!