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

You should be able to get everything that you want ........ Are you going to have a cabinet maker build it for you ? I suggest that you work with them and have them draw it up for you........Most cabinet makers are very good at working with their clients to get them what they want.

@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.

Suggestion: Never put the gas stove below the window and chimney against the window. It is ineffective as the air blown out is likely to come back in. At the least, it can be on the right or left side of the window with the chimney on the wall. Or the best place is on a slab on the left wall.