I really like your proposal, ByteCoin. I think it captures the intuitive notion of "incentivize publishing blocks immediately as the best policy".
... highest-number-of-transactionseconds seems like a very good criteria for resolving ties.
Thank you. The intention was also to provide an incentive for miners to make an effort to clear client's memory pools.
I wonder if transactionfee seconds is more interesting that transactionseconds?
I would be wary of allowing fees to change the merit of the block because it's low-risk for a miner to publish a transaction with a large fee immediately before publishing a pre-mined block which has its merit artificially inflated because of the influence of the included transaction's fee. Let's not forget that the purpose of a fee is to pay a fair amount for the time taken to verify the transaction and the space it takes in the block-chain. There are a variety of distorting effects that transactions with large fees have so I suggest that a transaction's fee for the purpose of calculating transactionfee seconds be capped at a value which is no larger than the transaction with the largest fee that the client saw did not make it into the previous block.
In other words, if a client received a transaction paying 0.01BTC in fees and then received a plausible block which did not include that transaction, then when the client receives a 10BTC fee transaction followed swiftly by a block including that transaction then the transactionfeeseconds of the 10BTC fee transaction should be calculated as if that transaction had a 0.01BTC fee.
The general idea behind this is to start to remove perverse incentives that arise from transactions with large fees while still allowing fees to buy priority service.
I am sensitive to hannesnaude's concerns not to encourage block-bloating but hopefully the existing schemes to calculate transaction priority will cope with that. Am I right in thinking that clients are likely to fail to relay and otherwise drop transactions with very low priority?
I must remark that I am very concerned that we do not introduce further incentives for miners to spam the network with transactions carrying fees in order to increase their own profits at the expense of everyone else. One important metric for the health of the network is the number of zero-fee transactions in blocks.
ByteCoin