you are requiring alot of changes tbh and that will have a low impact on those who are already rich.this is not the way especialy that later on boxes will become new currency and the zeni that already have no value will drop more because of the AH fee.. i really wanna solve this problem like you but this is not the way .id prefer no lagg over high prices anytime
Im suggesting and i dont think this is alot of changes really to solve or attempt to solve a big problem.
U have got one thing wrong this will make zeni of more value rather than decreasing it actually aside from zeni sink this is a main advantage of this let me explain
With this no one would dare to put imaginary prices cuz if they don't sell they lose 10% of their zeni so they will put a reasonable price say u farm zeni for 1 hour and farm somewhere from 200-300k and the said item with 10kk will be cheaper because of the 10% risk it might be lowered to 7or5kk u see how the zeni u farmed for 1hr become more valuable?
The lag issue can be solved by capping private shop zeni cap and lowered to somewhere about 1kk and people will have to use AH i mean surely they will AH as 1kk isnt enough