[bardd]

From the international perspective:

My biggest problem with this concept is time. There's simply not enough time in the competition season for 4 events in international regions.
The main reason Israel's regional is so early (week 1/2) is to give the qualifying teams enough time to prepare for champs, make travel arrangements and get money.
If you have 4 events the earliest you can have the teams qualify for champs (after the regional championship) is week 4, about a month before internationals. This means the teams would have to get enough money to fly 30 people +equipment 6,000 miles away, about 200,000 NIS from what I heard, in a month. That kind of money is hard enough to get in two months, good luck trying to do that in half the time.

Another problem, which is Israel specific, is that we can't have events on weekends, both because we have religious/mixed teams (so no doing stuff on sabbath), and because it'll make finding a venue a whole lot harder if not impossible (most places are either shut down or occupied on saturdays).
That means the events would have to be on schooldays (like our regional is now), and I bet no school would let teams miss three weeks of school for something as "unimportant" as robotics.