How to improve bathroom ceiling?

[diy_jen]

Hi, I did a bathroom renovation. We took off the cornices which created a gap. The tiler tried to fix but I feel it doesn’t look polished. Can someone help me with what the next steps would be? Do I need to plaster, sand and paint? Or can I just do caulking? 

 

  

 

[diy_vvv]

Looks like a rough job.