I think a comfortable distance between the island and the counter is around 42". It seems that you have only 30" between your cook top and the counter. I might be a little too tight. The wall between the entrance and the kitchen could be 4' long instead of 6', you would then be able to move the island a foot which would give you more room between the cook top and the island. Could you switch the location of the toilet and vanity in your dad's bathroom so your enter facing a vanity instead of a toilet which is a lot nicer.

How do you decorate your place, what kind of style, colors, and feelings? That will greatly influence the type of door you might want. Also, think of your budget, and whether you want to install it yourself or hire a professional (you don't need to tell us, just keep that in mind). Then look around Houzz, in the products page, they have lots of interior sliding doors and hinged ones, from elegant frosted glass in a dark wood frame, to rustic reclaimed wood planks. You may not want to purchase that exact model, but it might give you a better idea of what would fulfill your airflow needs without sacrificing style.

First of all, I don't think that furniture is comfortable enough to sit and watch TV, so the TV should be remove from that room, the purple wall paper and the purple furniture is too much, you should consider another color for that wall and the furniture against the wall it doesn't look good. What is that room at the end is kind of dark and I cannot appreciate exactly what is the purpose of that room. I'm a firm believer in skylights, we have skylights in the laundry room, kitchen, living room and office, they make a big difference. (if you cannot have skylights (or tube lights) can lights are a great option. There are a lot of great ideas from everyone. I can't wait to see the after photos.

Do they have to be paint buckets? I would think they would not be good for gardening? Maybe others will know more about that. But in the U.S. you can get 5 gallon buckets from some local businesses like bakeries, food store chains, places like those that regularly use items they get in the buckets. For instance a bakery usually gets stuff in 5 gallon buckets and often has to throw them into a dumpster as they can only save so many. Some businesses now sell them for a small fee, maybe 1 dollar U.S. each and some just give them away. I think the cost of shipping them to India would be more than the cost of buying them. You could try setting up a fund on Kiva.org and possibly get enough donations to purchase food grade buckets instead of using ones from paint. Good luck with this project and please update us as to your progress.