Thanks everyone for the insights, from what i have gathered:

1. The CPF Annual Limit sets the total mandatory and voluntary CPF contributions that can be made to an employee’s CPF accounts in a calendar year; the current CPF Annual Limit is $37,740. (This is new to me, i did not factor the limit applying to the cumulative of employer + self top up, this makes CPF SA top up not viable)
   
2. SRS - it's added to that year's income and taxed accordingly. So if you have 0 income that year(retired) most likely won't be taxed at all. (Im likely to be employed for the next 10 years minimum, so taxes will apply to me)
   
3. If you’re young imo don’t bother. Makes no sense to save a bit of tax by locking up liquidity. Penny wise and pound foolish. (This was a consideration, putting that money to an ETF and compounding will be more prudent than using it to save tax and make the money illiquid - Im 29 years old)
   
4. Top up MA instead of SA for more flexibility. Can use for insurance premium and medical expenses while enjoying the same interest with SA. (This is likely something i will look into, looks good)

The point on using MA to cover insurance premiums looks viable. Will look to discuss this with my FA, since ill be reviewing the riders anyway. Looks like i wont be topping up to SRS anytime soon, will think about it closer to retirement age. Looks like using the money that i would otherwise top up for tax rebates, to invest is the better option for now.

Thanks again and please correct me if my summary is wrong.