This is a tough one without re-doing the floors. Could you call a tile store? Maybe they have some type of treatment to 'rough up' the tiles. Also, since you have elders in the home, grab bars placed in well thought out locations might be a good idea anyway, along with skid-free rugs.

So many grays turn blue. after much trial and error for bdrm, bath and water closet , i'm happy with Benjamin Moore Horizon and Behr ultra in Burnished Clay. Neither look great on the card but they dry to a soft neutral gray. worth getting samples to try.

Adding taupe or beige to the walls, in most hues, would blend in too much with the draperies. I love the lavender in the bedding. It would pull the room together if you were to choose a grey paint that had elements of lavender or berry and silver. The color would be subtle, neutral, relaxing as well as refined. This slight shimmer will pull out the subtle nuances in the marble. As the headboard is already so interesting, it would be too busy to add anything too ornate on the wall. To open up the room and increase the light, you could hang a mirror. I would select an Art Deco style with metallic accents to continue pulling together the room. The marble is lovely, but combined with the sleek lines in the bed and bedding it creates a very smooth appearance. To create warmth, it is necessary to add additional texture. I would add a soft, plush or high pile area rug by the bed. How nice would it be to step out of bed on to that?

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.