Maybe i am looking at this problem in a simplified way, but if you have alot of overstays and too many extensions, why not apply for a new passport when you are in your home country, doesn't that eliminate all those nasty things in your passport?? or are they in a computer in thailand somewhere?

Immigration has a database where every entry, departure and etc is stored along with your personal information. They can and will do a name and date of birth search of it if you have a new passport. Changing passports is of no help at all.