Hi preethaa, I don't think there is any rule regarding the the built-ins. I've seen some spaces where they've done some really amazing things with built ins, like photograph murals placed on simple flat front cabinet doors. I think it depends a lot on the space, the style etc. Probably the safest bet is to paint the built ins the same colour as your trim. It is a classic look and you will not tire of it.

Send the wardrobes to the background. Paint them a satin sheen of the wall color.

Well I'll try to make a 3d of the room and upload it. But that will take some time. Thank you :)

What a beautiful house, Shahbaaz! I live in a similar house - a 150-year-old colonial bungalow in Kumaon. You have already received lots of excellent advice from better-qualified people, so all I would say is, keep its age and heritage character the central theme. The white tiles do clash, I am afraid ... flooring with terracotta tiles would echo the roof and look lovely. The columns and the arches over the doors and windows are amazing. But I'd say, leave it all chuna-painted - there's a beauty and softness to it. Don't let the painters add too much neel (indigo) in the limewash -- in the hills where I live, they put far too much if I don't watch out and the result is a harsh white. Natural lime has a softer, creamy look.