like going for a double Shock absorbers ... ?

Any race course drivers in INDIA can tell you the suspension of the MARUT l OMN l is superb for the size and cornering is where you will see full marks on this van.there is nothing you can do to make it perform like a race type or racing type you must be talking about load to carry RIGHT then you can increase the leaf suspension by max two leaves and that it or give your rear leaves a better tension. and thats about it.

yes
remove the driver and install in Bigfoot monster trunk

no you can not

you can modify but it wont be worth the huge amounts of money and effort.

Thats going to be a big challenge.

OMN l is not worth modifying since its chasis is not all that strong to stand any modifications.

The leaf plates behind is a tuf one to replace.

Sell it off and get a Alto Lxi

Maruti Alto Lxi is the Best in Mileage and sure to fit your budget.

Dont go for LX and end up with shoulder pain.

http://agnisharman.com/alto.htm