For income over 100k , what are some of the tips to help in tax savings (such as the fine balance on how much is going into SRS, top-up to CPF or any others)

Depends on what other goals you have other than tax savings.

For CPF cash top up, max tax relief from RSTU/VCMA is $8000 (self) + $8000 (parents etc)

For SRS contributions, max tax relief is $15,300.

For qualifying donations, max tax relief is 2.5x the donation amount.

Also if you have children or supporting retired parents, there are other tax relief schemes available.

Another thing to note is that mandatory employee CPF contributions also have tax relief.

The tax relief will offset the taxable income. Which could reduce the amount of tax payable depending on the tax bracket.

You can use the tax calculator on IRAS website to estimate for next year.