I also get the same problem when I try to create a network.
I think it might be that Rhino creates a smoother result because both sweep and network give the option to maintain curvature where as MOI does not have that option.
I guess what I'm asking is if there's any plans to enhance these commands or if there's something else I'm missing.
I apologise if all this sounds like bitching but I love MOI so much that I hate co-working with Rhino to get the desired result
Thanks