I'm really curious if there is another coin that managed to make an initial distribution to less than 73 people, I mean that if I was forced to distribute a coin to only 73 people, I would have really trouble trying to do so.
How did nxt accomplish this "feat"?
With a public offering. Those 73 founders had to buy their initial NXT with bitcoin. The hope was that 73 people was large enough to avoid problems of being too few (eg, collusion, all apples in too few baskets), and small enough to avoid the problems of being too many (eg, bystander apathy). One problem with distributing to many more people is that they tend to sit back and let someone else make the coin valuable. If you give it to them for free, then they naturally consider it worthless. What's needed is people who will be active, in funding development, marketing etc.
If we also take into account the "silly"1 btc "limit" we can be sure that the insiders sent btc from multiple wallets and this makes their numbers much much less than most people think and the supposedly 73 number!
Steps were taken to prevent that. (This wasn't publicised at the time, for obvious reasons.)
That said, I don't think anyone has ever done a taint analysis on the Bitcoin. It's not too late; the information is in the blockchain. It would be interesting to see whether the BTC used to buy initial NXT did come from related wallets.