4) remove the 21 000 000 limit so there can be a unlimited number of coins
The 21million limit is only imposed by the rewards distribution over time, so, if point 2) is satisfied it will automatically satisfy point 4)
Not actually true. The code assumes 21 million in many places, not literally that I know of, but this limitation plagued IxCoin in that it would crash in 2015. A second limitation is bitcoin networking can only handle 64-bit integers, so this idea would break in 2.1 trillion years. Wishful thinking, I know
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