When dealing with north america, the timezone EST is the best to use, and hong kong is 12 hours away. What this means, if times are set using these timezones, hong kong is gmt+8 (i think, googled and stuff, but i could be wrong still), if tourneys were at 11am and 11pm, i think everyone every where around the world would be much more accommodated. Still use a 3 hour rotation, so go 10-12. There are always more people on during these times anyway.
-edit-
after losing in this weeks eastern tourney in my first match, ive come to a conclusion.
the special rules dont do jack squat, so i say just do away with them. people will still use one of the common decks no matter what, might as well just open it up and allow every card every week without any restrictions. no matter what the special rules seem to be, i always run into the exact same bunch of decks week after week, no one seems to take the special rules and make decks from them, they just take common decks, with slight tweaks adding in cards if cards are required, or substituting a few if any are banned. its boring, and its rather irritating to see these decks when we have special rules, and usually the rules are bad anyway, because they allow these decks to be used every week.
with such a limited amount of cards, sure, you might make the excuse that there are only so many decks people can play, but that is just plain wrong. there are lots of decks that can be used, but its roughly 5-7 that are used about 80-90% of the time in tourneys. remember when everyone started to complain about how all the arena decks are so unimaginative? they still are obviously, but same goes for the tourneys any more. the rules suck, they dont change much of anything and people are not being creative with the rules that are given.