It might also solve several problems at once. I think it would:
- make the number of stakes you claim more important than the amount of the stake transactions (atleast once there are lots of transactions flying around and the destroyed coinage is mostly coming from the included transactions and not the stake transaction itself). This would then encourage you to keep the client running to claim as many stakes as possible and to include as many transactions as possible.
good catch. Indeed - generating more blocks from the same stake will give you more bang for the buck, if you can claim a percentage of the destroyed coinage from the included transactions as a reward. Thus you have an incentive to have your stake existing as many small outputs. An indirect consequence of that is that you need to have more uptime for the stake - because smaller stakes have larger sampling requirements, i.e. need more online time.
That incentive may be so strong, that you may not have to modify the 1% per year reward at all to encourage POS miner to be online.
E.g take block 16924:
Coin-days Destroyed: 47119.621896
POS Generation: 0.43 Total (503.69*0.01*31/365)
Stake: 503.69
If you allow for 1%/365=0.000027 transaction reward per block you have an additional reward of
47119.621896*0.000027=1.27
which is almost three times the actual POS reward. That means that a POS miner which is always online may easily effectively generate 3-4% on the used stake, which suddenly makes it much more attractive...
A change in the POS incentive structure like above would also likely put the discussion about the lack of transaction fees to rest:
https://bitcointalk.org/index.php?topic=114664.0