Absolutely — you're spot on to think beyond just the flat 30% on gains. In India:

Losses can’t be set off against gains or carried forward, so even if you lose money, it won’t reduce your crypto tax bill. Transaction fees, gas, or exchange charges are not deductible when calculating taxable profit. Staking, mining, and airdrop rewards are taxed as income (at your slab when received), and then 30% again on any later sale gains.

So yes — fees, how losses are treated, and the type of income all matter and can meaningfully change your total tax liability, not just the headline 30%. Keeping good records is key.

Hii,
I am a senior citizen. In the old tax regime, there were special advantages in tax rates for senior citizens. Does the new tax regime allow any special exemption for interest earned by senior citizens from savings or fixed deposits? Are deductions on medical insurance premiums still available for senior citizens in the new tax regime?

As an NRI, you can not open a new PPF account. But if you had already opened your PPF account when you were an Indian resident, you can continue investing in it until its maturity. You can deposit up to ₹1.5 lakh per year, and withdrawals are allowed as per PPF rules.
And once your PPF account completes 15 years, you cannot extend it further. Extensions beyond 15 years are not allowed for NRIs.