There is room for an island if you don't require an eat-in kitchen. Personally I would switch the kitchen and the drawing room to allow some shared daylight for the dining room which isn't the best as there are circulation around it all all 4 sides.

there is no perfect dimensions for an island. Try to organce space subdividing into smaller cabinets of 60x60 cms which is the max space for a structural division and works for seating area as well

coming to the dining area..yes id say you remove the seating entirely and concentrate on a foyer area since you already have space for a drawing room on the floor.. id suggest erecting a glass and marble wall in line with the wall that runs between the pooja room and the bedroom..say a bit of marble-glass-marble-glass-marble.in this case you have a small foyer area demarcated by this wall feature.you can deck it up by placing a nice console table in front of the central marble wall with a nice mirror to reflect the space and make it look larger or a sculpture with beautiful bracket lights on either side to accentuate the same.and on the backside of this wall you could have a crockery unit with a huge painting or a cluster of family snaps above it. if you could brief me a little on the look you're adapting for your house i could suggest some more treatments for the walls.if you want to avoid using too much marble you could also opt for a marble wood and glass look where you could take out some concealed storage for shoes etc. regarding the drawing room - what about a huge 4 seater in the center instead of 2 - two seaters with a table in the middle as in the plan..if you remove the central coffee table maybe you could replace the single seater with a chaise for 2 and also replace the 2 center tables with a nice long table in the center with an area rug running below it..if you could help me with the room dimensions maybe we could add 2 pouffes in front of the 4 seater so it creates more seating and doesnt obstruct the view if you plan to put a TV on the wall. what look do you have in mind for your terrace garden ? something zen or a little rustic toeing on the lines of the contemporary ? sorry for the late reply as i was travelling.. hope this helps! :)

@Cornerstone design studio: Apologies for making big post; thought that more info will help. @Rupal ji, If it sounds like I dont need any changes; my apologies for that. Let me put it in short,"I am looking for options that give modern facilities without leaving good things from old charm/ comforts. " Thanks for the straight forward comments. I shall try to edit my original post to make it simpler and that looks open to new ideas.