Your last picture is the ceramic package. Typically this is on early versions of the logic board. But since Apple sourced components from a variety of vendors, anything is possible. This appears to be a later board due to the large Apple logos on the RAM chips.

The blue resistor is the piggy back fix I was mentioning. It was first applied in the field during repairs, and then kludged onto the OEM boards at the factory.

The Hytek chips are similar explanation, the orange chips on the Wikipedia pic likely supplied by another vendor. There may be a way to date boards by specific components, but to date nobody has done a comprehensive survey of the individual components across the manufacture dates.