The Order 66 arc was great, and really made you care for the loss of the two clones, Fives especially. By deduction it was obvious that the Kaminoans would have to be involved in some shady dealings with the clone army and their programming, but I didn't know just how deep their involvement went with the Sith.
The programming bit just makes the story of the clones even more tragic than it already was. We already knew they were programmed to be absolutely obedient, but even then it was cold how ruthlessly they turned on their Jedi comrades after serving together with them for so long, without even a shred of regret it seemed (barring some exceptions in the EU). Now we see that the programming extends beyond a simple need to follow orders into making them outright despise the Jedi. The horror on Five's face and in his words when he realizes what had been done to them and what will eventually happen was sold really well.
I was surprised that Palpatine made such a bold move and so openly attacked Fives, even with him being discredited. That shows how close to having their plans unraveled they were for him to take such direct and desperate action.
As mentioned, the production values were excellent. I loved the artificial planetary ring (although having "ring" in the name of the planet was a bit silly) they were fighting on, and the zero-g fight on the shuttle was impressive. The new flying battledroids are cool. The Kamino sequence was impressively rendered as well. It was great to get to see the medlab where Anakin will become Vader again.
All in all, a very promising beginning for this final season. I look forward to seeing the rest.