If we create our own blockchain like bitcoin who will be the miners to mine new coins ? If we create fork than there can be no ICO for that ! in fact for even a new coin like bitcoin there can't be an ICO as it needs to start for 0 to mine (so no pre coins means no ICO). If we create fork of bitcoin itself then people with bitcoins in their wallets will get it so no meaning of ICO there.
If we create a coin with some premined quantity for ICO investors and rest quantity getting mined with time... who will be miners... a few nodes may not serve the purpose of many transactions going on so network may get stuck as transactions increase. But still its one of best as per me as the coin will take time to rise we can make with one bigger blocks size (its obvious hardly anyone would spam the blockchain of our coin and to reach a number of transactions per sec it will take lot time... till then many changes in it could have been made). Same for mining ... people who will understand that the coin has a value and its to rise with time ... can use their PC for mining and the increasing demand will lead to increasing value of coin which will later lead to increased transactions and the increasing value will lead to more people setting up nodes for mining so basically a balance will get created with time.
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