If you think the Chinese vase at the base of the table may be valuable, you should take it (or the photos of it) to a reliable art and antiques appraiser in your area. You aren't likely to get a reliable appraisal on line.

Actually, there is a designer who has designed a sofa/table piece. You can see it here - http://kononenkoid.com/julia-kononenko-projects/convertible-sofa. That may help you visualize your planned project.

If I am having trouble finding a rectangle glass top table I usually order the glass from a local (to the location of my Client) glass shop and then the base from one of my furniture vendors. a dark table with your light chairs should not feel dark given that it is in a room with what looks to be lots of light with the large glass door and side window. I do think the glass would be perfect for the area. What size table are you thinking will fit the best in the space and for your needs?

you should take place your dinning table near to the all by which u can get a lot of space to decorate these place much more beautifully.