Few checklist:
Suppose your insurer name is 'ABC Insurance' (replace with your insurance company)
- Check whether you can pay premium in any third-party website or own insurance portal only.
- If it is third-party website (ex: paytm, phonepe, amazon etc.)
- know the reward points/cashback of your cards in those sites.
- also need to know more about which MCC they're providing and reward rate/cashback for that MCC.
- If it is the own insurance portal, then 99% it comes under 'Insurance' MCC only, so know about the reward rate/cashback for that 'Insurance MCC'.
- If it is available in third-party websites, know about gift voucher options available for those websites and respective reward rate/cashback for that option.
- make sure that gift voucher must be able to redeem for this insurance premium spends.
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Since, you didn't mentioned about your insurance company or it's available third-party websites, we have to assume for base reward rate for insurance category (for optimal suggestions, always mention those to get best reward rate/cashback because there are so many ways to purchase vouchers or spend on those websites to get full rewards/cashback compared to direct payment).
Because, Ex: Legend gives 0.7% insurance payment directly, but if that is available in amazon and one can able to find a way to purchase amazon vouchers during weekend then it can be increased to 2%.
Flipkart 0% for direct insurance payment, but if one can get paytm voucher without any charges it can go 1.5% (can replace paytm with whatever website you prefer).
Suggestion (not related to your question): you should close apprx. 10 cards (even if it is LTF) in your list, those are not providing better rewards and you won't get upgrades easily if you didn't spend much on those cards. Ignore if irrelevant.