You have some solid points.
Also, if a item limit were put into place (i.e. you can only buy x number of items every 12 hours) that may also help.
Maybe..
- 1000 total level 1 high-item/12hr
- 1800 total level 2 high-item/12hr
- 2100 total level 3
- maxed 4
etc. just a thought though.
geat idea, i support on this