I suggest that you try to find some plastic bins that are almost see-through and fit the space. That would be two for each of the lower shelves. You could pull out the bins to see what is inside and even label the outside. Or you could cut your plywood to fit the space and support it on the built-in shelves with bricks or purchased legs. The problem with this is that things in the back would be even more hidden than they are now. Then for the upper left you might be able to find a set of shelves that would fit. For the top right, I would put big soft things that you can grab and that won't hurt you when they hit you on the head! This might be extra bedding, towels, out-of-season clothes. For children's clothing I like to fold the whole outfit together, so that one doesn't have to hunt for the "matching" part. I think that your cosmetics could be in a small box that fits on top of other bins or clothing on shelves. Good luck. This will take some experimenting, but something will emerge.

Not sure how the kitchen is laid out, but it seems rather large in comparison with the main living area.

What are those red curved lines? The measurement is also not clear. What i understood with this is that , You should have two different rooms - one is formal drawing room with only sitting area and for that you need not provide a partition as it should look grand from your entryway and second one should be the living room. There you must give a partition between both the rooms so that the person sitting in the drawing room cannot peek in the living room and it'll be kind of privacy as other area will also be not directly visible . By giving a partition you are messing up the passage way more.

@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.