I am planning for ICO, which provides services. User need to invest some x amount of money to buy token.After buying token their will be a grace period for 10 days to generate revenue and expect returns on month basis for next 10 years. Which model of ICO is fit for this ?
Swarm City is good for off-chain 'transactional' activity which is secured by individual reputation, however, in this case you are looking for a longer term interaction between those providing investment and the activity generating a return.
It looks like you need something like a Kickstarter which is what https://www.fundyourselfnow.com/ will be trying to do.
They seem to be more geared to smaller projects vs. WINGS for example.
They do charge fees for their services, so you will need to do the math if it's right for you. This would be much simpler than creating your own token and smart contract.