The largest advantage that the MiG-29 ever had was its leap forward in generation from the MiG-23 series aircraft. The early aircraft, although quite manuverable and with some great weapons for their time, almost couldn't be considered modern combat aircraft of the day. Awful visibility, avionics, radar, engines, range, maintainability and manufacturing workmanship. It was at best a capable classic Soviet ground controlled day fighter. A Soviet MiG Factory demo pilot told me the same during a North American tour back in 1988(?): "The MiG is the best airshow airplane in the world, but I wouldn't want to have to fly one in combat." When I asked what he would prefer, he smiled and pointed at the Viper parked across the ramp, and addresed each of the issues that I mentioned above.
Yes, the new MiGs are a lot better then the Fulcrum A's, but let's put it this way - there was a lot of room for growth.
If the MiG-29 is as good as the F-16 or F-15 for half the price, as you say, where are they all? For that much capability, at that price, somebody would buy them. List the customers who have chosen the MiG-29 over - I was going to say a Western combat aircraft, but list the customers who have chosen the MiG-29 over anything if they really had an alternative.
Mike