I've come up with a compromise on the issue of bulletin stacking. It is basically as so:
1) Bulletins will no longer stack;
2) Players can buy duplicate bulletins with supply points
3) The game normally does not allow stacking, but people can make mods that allow them;
4) As a result, people who really want to stack bulletins, can still do so, they just download and use those mods in custom matches.
From the looks if it, the system removes stacking simply by automatically salvaging duplicate item drops, so all Relic needs to do is not automatically salvage duplicate items (or at least, not the bulletins) but turn off stacking.
If you want it to come with an angle of challenging, the game does automatically salvage all duplicate items when released to live game, but people who want duplicates can just use the supply to re-buy whatever they want.
What do you guys think?