It's clear that our opinions differ a lot. As for the WoE question.. it's not the same item, it's the same effects yes, but a different item. That's what differentiates a LOT of gears and prices on this server. (Compare the different kind of SGWs. Huge price differences, yet the same effort to get them and the same effects. Just saying that looks decide prices a lot on FRO).
Again in my point of view it's not monopolized because of the prizes. Heck there's a huge load of people that would love to get an item worth 6k coupons that is this rare and better looking than the other rucksacks. It's the fact that the slightly smaller guilds wont stand a chance in GvG because 95% of the massively geared people are in 1-2 guilds that took over GvG. Boosting up the rucksacks will only make the current monopolize guilds even stronger and might even discourage people from joining GvG even more because their chances have gotten even slimmer.
Nearly every change in every wanted item influences it's price. If you boost an item like this of course it would get more popular, of course more people would want it. Yet the supply stays the same ( or LESS even if what you're saying is true and more different guilds will join, certs will be spread over different guilds and it will take longer to make the rucksacks. ). This means the supply will stay the same or get less, while the demand gets bigger. This in simple economics causes inflation and will cause the item to raise in price because the item will be "more rare" and "very much wanted".
The 'mere' difference you're asking for is fine by me, But removing the movementspeed reduction is a mere difference, removing the movementspeed and giving it such damage bonusses is no longer a 'mere' difference in my opinion.