Thanks.

Some consequences:

None of this requires thinking of Nxt as a currency (or in fact, Nxt at all. I've tried to avoid terms like "blockchain" which I suspect have a lot of pre-established "freight", I prefer to talk about the more general concepts like "version of history"). Nxt, or rather effective stake, is just how often you get to update a version of history, i.e. how much say you have in the history. Right now, I think of Nxt as a way to come to consensus on a version of history. Not just a history of $ transaction, but potentially for any events that can be recorded digitally.

If Nxt is not a currency, then it doesn't make sense to talk about profiting from requesting events to be added to versions of histories (transactions). It does make sense to make such requests free. But in practice, in Nxt, current technology is still limited, we need to limit (ab)use with a cost to transactions. If we are to have costs, it makes sense for such costs to depend on the type of tx being sent (as in fixed fees), since different txs have different costs in terms of space and processing requirements of the entire network. Rather than depend on the amount of Nxt you're sending (as in proportional fees), since the more effective stake and influence you have, the more you should be able to do.

(I think jl has already talked a lot about these last two paragraphs, just in different terms.)