We bought a king single for DD, so there is enough room for one of us to lie next to her (when needed). I don't know what the answer is, i know what you mean about your LO needing to be ready, for you to make changes. I'm the same.

My LO was showing signs of being ready when we moved her into her own bed and room a couple of months ago. DH (also a shift worker) had some time off work when DD moved, which really helped with getting her established in her room. I am more a morning person than night person, but DH was able to sit with her when she woke (we toook turns). SOme nights she wakes, and if we get to her quick enough she will usually go back to sleep pretty quickly. Other nights, she comes in with us but this is getting less often.

Have you tried moving DD once she is asleep?

good luck