If you want to trade KLCI, go for FKLI.

ETF (2 in the market) is simply too illiquid locally.

For normal time (most of the time, except during very bullish scenario, the rollover is advantage to the long (buy) as next month contract a lot of time is lower (range from 1-3 points up to 10 points in market down turn time) compared to spot month.

Not feasible, as longer contract is illiquid. For spot month, you get more liquid and advantage by having spot or next month contract then roll over it. You just incur the commission charge of Rm50 between the rollover while let you have the flexibility to trade in between compared to longer contract.

Yes, per contract.

But the differentiate in spot month and next month contract (if spot month price > next month) will let you gain back the RM50 if there is 1 point gap between them. So if there is more than 1 points gap, you gain more than lose in this kind of scenario.

A lot of people don't know or realise if one is actually holding a contract of FKLI, it worth 50 x index.

So if the index is 1000, basically it worth 50K per contract but you just need to pay the initial margin, a few K (as it varied from time to time) to own those contract.

For long side,
Basically you are risking 50K (because index cannot go beyond/below zero), not a few K of initial margin you paid for the contract. So you need to have spare money to withstand the margin call if market goes against you.

For short side,
you are risking indefinite amount as there is no limit for the upside at least mathematically

Don't look at a few K initial margin as you investment, actually it is not.

Futures is a leverage tool as well.

For ordinary and less sophiscated people that wish to invest on KLCI long term as title per said, I would suggest using ETF or index fund (although there is no pure index fund but at least 90% alike) like Jordy suggested, as for futures it you don't sure what you are doing, it can kill as we know leverage is a double edge sword.

You don't close the contract, you don't lose a single cent, just topping the margin doesn't mean losses.
It is unrealised losses and those margin money is still within your accout, just the money being earmarked by the investment house for their protection.