Predictable Lunar/Islamic calender

How to celebrate Islamic festivals simultaneously across the globe is a dilemma we're facing these days. Following are random thoughts which came to my mind as a solution to this problem.

1. A predictable lunar calender can be made for any location in the world.

2. As per Shariah we have to fast and have Eid when the new moon is sighted. There is no known  radius of applicability of the moon sighted for changing lunar calendar date in Islam. The geopolitical boundaries we talk about are not Divine. If we would have been part of an Islamic Union with our capital at Mecca, moon sighting there would have been applicable here too.
 

3. We need to decide a location in the world which could work as a reference point for the proposed lunar calender. For religious reasons Haram Shareef is the best location and people would have less problems with that. However any other site can be agreed upon and this can be a place where the moon becomes visible at the earliest. 

4. At the proposed site a size of the new moon could be agreed upon to be labeled as Visible and Sighted with naked eye. 

5. A predictable lunar calender could be made which would be applicable to the whole world. We don't have to actually see the moon just like we don't look at the sunset for azaan for maghrib prayers, instead we just look at the clock. 

6. Whenever new moon reaches the Visible and Sighted size at Haram Shareef or the agreed site it would be applicable for the whole world because nowhere there has been any mention of radius of applicability of the moon sighted in any location. Moon sighted at one point can be considered applicable for the whole world as the geo-political boundaries do not matter when one rises above the level of Earth and look at things from a universal or planetary point of view. 

7. There is one point against the system namely different time zones and people often mention prayer time differences as an evidence against this system but I feel that is a different issue altogether and depends on daily positions of the Earth in relation to The Sun. Even a little deviation at places should be acceptable for making a predictable Lunar calender. Some places might not have moon visible at that time but when it is sighted at one side it would be extended to other places too.

8. This suggestion needs to be discussed at OIC level and a solution found. That could be taken as some performance of this otherwise toothless organization. 

Comments are welcome!