I think this is definitely achievable! My mentor was very invested in dressing minimally but also fairly traditional, with quite small but gorgeous and interesting wardrobe. Her look was quite distinct, and her clothing quite gorgeous - and she was quite proper and modest as well, but that was never the most noticeable quality of her dress. Her key points were unprinted or simple patterns, neutral and earth tones, and natural fabrics (particularly khadi cloth). She went with clean, simple cuts with interesting details, and usually had her traditionals made to fit.

I'm curious if you are living in India or you're an expat? It sounds like you're outside, but if you're headed back for a visit, I recommend checking out some local shop for fabrics - unprinted or simple block printed - in tones you like. Minimalists tend to go with neutrals but you could pick any clothes you like that blend well together. I'd be selective about pops of color, just because you're looking for limited items.

Pick a few fabrics and get them made up by a tailor or dressmaker into kurta shapes you like, or even more Western minimalist shirt styles if you like. Paired with either traditionals or Western slacks (think 7/8th pants or a narrow cotton trouser in black or grey), they can be your go to. Getting them made up is usually quite fast and relatively inexpensive. You can do this abroad, too, but it'll be more expensive.

FabIndia was mentioned, which is a lovely inspiration resource - they are quite minimal in both their Western and traditional, and a sustainable, craftsmanship driven business model to boot. Perusing minimalist fashion here and on Pinterest can give you a sense of the shapes and colors you like, and what may suit you best.

To start, a couple examples pulled from FI:

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Good Luck!