I can easily imagine in near future attackers willing to spent 5-10% of all the NXT value, maybe even more in the first months. In far future if NXT suceeds this % will indeed be smaller, but the amount of money will still grow because it will be worth more.
So for many people to run their nodes the transactions they earn must be quite a sum, its hard to calculate people willignes, but lets say the total earned fees per month should be around 1% of all money existing. This is A LOT, too much, transactions will be too expensive. You can not have 1% of money existing to be transfered per month just for the sake of transactions.
And another thing even more wrong with NxT, its 100% premined for gods sake! Even if it is not a scam per se it still is a scam, because no way how you turn this about, the original holders will profit A LOT MORE than "forgers"/miners that are responsible for coin stability. At bitcoin(and most other coins) all the miners have equal earning posibility depending on how early the get the coin, but that is not the point, even bitcoin has a problem of early adopters having too much. A true crypto curency should have earning posibility that is 100% aligned by the amount of money and the time at which they invest in curency. In a LINEAR WAY, not this premined, exponential, root,...shi...