I see a potentially good idea, but too many things can and will go wrong.
First off, everyone else is right- plat is how STS makes money. Giving away plat in 'excessive' amounts as suggested would essentialy be a loss of money.
Second, CTF would be even more ruined. Think about it, people already flag farm. Giving them REWARDS for flag farming, which already is against the purpose of CTF. is ridiculous. Can you imagine the chaos and tension that would create? What about the extra amount of dummy farmers in every room? CTF, and PVP in general, would be unplayable during this event!
Also, Hail brings up another point. What about the upcoming market crash, especially for vial farmers! Nekro, and vials, would decrease in price to not even be worthwhile to farm: rendering the Planar Arena useless.
I see the idea, but I disagree with it. Good luck pursuing it!