1. Insurance and unit trust are more for capital maintenance though they have risk. These instruments dont make you financially independent.
2. IMO, one achieves financial independence when one can choose to quit his job or biz without any worries in meeting ones cost of living for the rest of his life. You will feel blissful when one feels unaffected by frustrations in employment or biz.
How much is enough you might ask. It really depends on individual life style and level of contentment. Sam has given a quantum of the lower extreme. But given the way things are going in sinkieland, I may add one or two hundred thousand in hard cash for the lower end if you choose to stay. I never bother factoring CPF in personal financial plans since day one.
3. Even if you have multi millions, no one has to know of it. So where is the queue? Personally, I know of a senior person who has been working as a clerk. He learned and speculates small amounts in the currency markets for many years, and he has accumulated afew millions. Yet he is contented living a humble existence. IMO, he is a person with substance relative to his supervisors who are loud mouth show-offs with debts to service.
Maybe you can ask "the many", can they just show their employers the middle finger and quit, or walk away and sell their biz now, with out any financial worries for the rest of their lives.

Greed is another matter.:(
I heard this concept of financial independence for so long and from so many people that I cease to understand what it means. The many who approached me couched it in terms of insurance and unit trusts. I bought my own and do not feel it makes me financially independent.
But "multi-millionaire" - that I can understand. In fact, if you are a multi-millionaire, you will find that there will be a long queue of damned sinkies waiting for you.