After carefully looking at the existing floor plan i realized one might not be able to play around in the bath area because of building code drawing for the plumbing especially since the piping (water supply and drainage pipes) might be coming from the ground floor all the way to the top floor.
So i would advise against messing with that. I have tried to also incorporate everything you have request for especially the reading table and dining area, I was able to come up with a breakfast table attached to the open kitchen for the dining. Anything grand will choke up the space and make it messy and crowded with no circulation space.
You can look at all of the 3 options I've created including the 2 bedroom option which i think works perfectly.
I will create an interior rendering for the one bedroom option. will send that as soon as i get the chance but i think I've been able to capture everything you want.