I would tend to agree with the architect because they have the vision of the entire space. This is a discussion you should be having with him/her so they can explain why 10 feet is better, or they can adjust it to your preference.

Hello Teja, for the luxurious look add wood with polish and pop to balance it . Select some drop lights in one of the corners, indirect or hidden Led lights and some spot lights and its done.

Ok Monika, for the beam running in the middle of the room you can clad it to make it a part of the design but it needs to be planned properly. You may need professional help there. These attached suggestions should hide the beam. If you do not get the theme in the pics please feel free to call us to understand the suggestion. Thanks, Nitin Cornerstone Designs, Bangalore.

Jaggi, while it depends on the overall depth of the coffer ceiling but as a thumb rule you can leave a safe gap/height of 9-9.5 ft from lower end to the floor. Thanks, Nitin Cornerstone Designs, Bangalore.