With bitcoin likely to increase significantly over value in time, a fixed fee per byte would tend to have the effect that it becomes more and more expensive in terms of real world value to create a large block.
not sure if this is a showstopper or not. just pointing it out.
That is a good point!
I haven't checked the statistic to back this up, but I'm guessing that the dollar value of the median transaction within a block is fairly stable over time.. The median transaction within all blocks over the last 100 blocks could be used to find an average, lets call this the value "A".
Lets just say that the "right" amount of fee per bite is 1/10000 of A, lets call this the value "B"
Several people have rightly pointed out to me that miners can just 'fake fees' by paying them to themselves...
I'm therefore thinking that instead a miner should be allowed to create a bigger block if the median fee per bite paid within that block is greater than B+20%
(NB: please do not give to much attention to the numbers I have used.. They are just for the sake of examples, and are most probably the wrong numbers)