The difference is the amount of coins going into circulation directly reflects the difficulty. No other coin (that I know of) does this. Yes the difficulty does determine how much the individual miner may receive but the amount of coins being generated is all ways the same.
Other then PPCoin and Novacoin (which both decrease block reward with diff decreases)?
Wow, writing the above made me think... What if someone made a coin that changed the block time depending on the difficulty? Say making the block time longer if the difficulty went up. (blowing my own mind right now)
Block time meaning target time to block? As in, effective difficulty would just be a factor of the real difficulty?
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Getting rid of KGW fixes the re-org and block reward manipulation attack. It also leaves the coin open to huge diff swings (not that KGW fixes this entirely - just look at luckycoin's recent situation), which is a pretty big problem unto itself.
Changing the block reward scheme destroys the novelty of this coin, in my opinion.
At this point, I don't honestly see a solution that will see this coin survive the year that doesn't involve re-writing the block reward scheme and protocol to issue rewards in the next block (which would be truly novel and awesome).