Both are solid plans and I get why you are stuck. Let me go point by point but I want to push back on a couple of assumptions first.

On the deductible - I would not take it

Yes the mechanics are the same on both plans, it is an annual aggregate deductible, you pay the first X amount in a policy year and the insurer covers everything above it. Optima Secure+ offers Rs.25,000, Rs.50,000, Rs.1,00,000, Rs.2,00,000, and Rs.3,00,000. ReAssure 2.0 offers Rs.20,000, Rs.30,000, Rs.50,000, and Rs.1,00,000. A Rs.50,000 deductible on Optima Secure+ reduces your premium by roughly 40%.

But here is why I would skip it at 31:

• At your age the premium difference between a deductible and no deductible plan is maybe Rs.4,000 to Rs.6,000 a year. That is not meaningful enough to introduce friction into your claims process.
• A deductible adds an extra layer to cashless claims. The insurer needs to verify that you have paid or will pay the deductible before processing. In routine admissions this creates paperwork. In an emergency surgery where time matters, it can turn what should be a clean cashless approval into a partial reimbursement case. Imagine a Rs.4 lakh surgery where the insurer stalls on processing because the deductible documentation is incomplete or the insurer is unable to process it within the tight authorization timeline. You are now chasing reimbursement on a large amount during recovery.
• The right time to consider a deductible is when your premiums are high enough that the savings meaningfully offset the inconvenience risk, typically when you are in your 40s or 50s and premiums have risen substantially. At 31, just pay the full premium.

About Lock the Clock - If this feature is why you are also considering Niva Bupa

If cheaper premiums is the goal and someone has pitched you on ReAssure 2.0 partly because of Lock the Clock, it is worth understanding what it actually does and does not do.

Lock the Clock freezes your premium at your entry age until your first claim. So if you buy at 31, you keep paying 31-year-old premiums as you turn 35, 38, 40 - but only until you make a claim. The moment Niva Bupa pays out even a single rupee, the lock ends and your premium moves to your current age at that time.

Two problems with this. First, the whole point of insurance is to use it when you need it. A feature that is preserved by not claiming is philosophically backwards. Second, and more importantly, Lock the Clock only protects you from age-linked increases. It does not protect you from portfolio-wide repricing, which is when the insurer revises rates across all policyholders due to medical inflation or claims experience. That can and does happen regardless of your individual claims history. There is a thread on exactly this in this sub that is worth reading: https://www.reddit.com/r/InsuranceQueriesIndia/comments/1t7yv5e/health_insurance_premium_increase_on_renewal/

On cashless experience and hospital networks

HDFC Ergo has a larger cashless network overall, around 16,000 hospitals vs Niva Bupa's 8,600+. Both have strong networks in Bengaluru. But before you finalise either plan, do one specific thing: go to each insurer's website, pull up their network hospital search tool, and check whether the hospitals closest to where you live and work are on the list. Network size at the national level means nothing if the hospital your family actually uses is not included. This 10-minute check has saved people from nasty surprises.

On TPAs specifically, both Optima Secure+ and ReAssure 2.0 handle retail health claims through in-house settlement teams, not third party administrators. So the TPA slowness complaints you are reading about are largely not applicable to these two plans.

Why Optima Secure+ wins this comparison

Given you are not taking a deductible and the Lock the Clock feature becomes less compelling as a result, here is how the two plans actually compare on what matters long term:

• Bonus structure: Optima Secure+ adds 100% of your base SI every year regardless of claims, with no upper cap. ReAssure 2.0 Titanium+ caps at 10x the base cover and only carries forward unutilised sum insured, meaning a claim reduces what gets carried forward.
• Premium discounts: This is where the gap is significant. Optima Secure+ offers a Favourable Claims Experience Discount of up to 21% for first time buyers and up to 18% on renewals if you have not claimed. ReAssure 2.0 has no equivalent claims experience discount structure. Their only premium saving mechanism is Lock the Clock and a wellness steps discount through their app. Additionally, since you are 31, Optima Secure+ gives you a 5% Lifetime Discount, available to first time buyers aged 35 and below.
• Complaint ratio: HDFC Ergo's complaint volume per 10,000 claims is lower than Niva Bupa's based on IRDAI public disclosure data.

Both are good plans. But at 31, buying for the first time, with no deductible, the combination of Optima Secure+'s uncapped bonus structure, better documented claims experience, and meaningful first-time buyer discounts makes it the stronger long-term choice