The first plug looks like transmission oil being sucked into the motor, through drive side crank seal or possibly damaged crankcase gasket.
All CDI based ignitions suffer from reduced spark intensity over the years. This is due to the capacitor degrading, which results in less power going to the HT coil when the system is triggered.
On almost all AC systems with an external CDI unit, its possible to replace them with a cheap pit-bike part costing less than $20.
Finally its very difficult to get accurate plug colour readings when modern fuels are being used in 2T motors, but using a specific race oil such as Castrol XR77 developed to help give accurate readings, will make plug readings much less a matter of pinning the tail on the donkey as it were.