For me, Slaves of the Republic was an enjoyable episode that didn't suffer from the flawed suspense of its predecessor. I don't see any major faults with it, and feel that it serves its purpose as a plot thickening middle episode to this arc. The thing that stood out to me the most was the artistry in the animation of Slaves of the Republic. The look and feel of Zygerria was well executed, with heavy Egyptian and middle eastern aesthetics, especially in the urban capital. The only other city that feels this fleshed out to me is Coruscant. The designs of the character models were equally well done, from the slavers' helmets, to Ahsoka's outfit, to the Queen's regal attire. The entire look of this episode really impressed me.
With a captivating environment, the only thing Slaves of the Republic needed was a solid plot, and I felt it had that. Sneaking around behind enemy lines in disguise on a secret mission seems very Star Wars in my opinion, reminiscent of the rebels' infiltration of the Death Star in A New Hope and Jabba's Palace in Return of the Jedi. This whole episode felt like an Original Trilogy story to me. You could easily replace Anakin, Obi-Wan, Rex, and Ahsoka with Luke, Han, Chewie, and Leia. The reduced focus on the politics and battles of the war added to this illusion of timelessness. There was also a clear reference to Return of the Jedi, with the heroes nodding at each other, and then R2 shooting sabers into the air in the slave arena to the tune of an iconic John Williams theme.
It was really interesting to see Anakin try to seduce the Zygerrian Queen. Ahsoka's apparent disgust at this tactic added a healthy bit of tension between the heroes that may come in to play down the road. Perhaps this "charm" that Anakin seems to posses all of a sudden had some involvement in the quick advancement of his relationship with a certain senator. What was really fun to watch though, was seeing the tables turn, and the Queen taking control of the Jedi, foreshadowing future events with Palpatine. For once even Dark Side interrogation couldn't save the "Chosen One", and he his attachments are being used as a leash and prod.
The Zygerrians themselves were very interesting, resembling an ancient slave trading society ruled by a monarch. The Queen makes for a strong female foil to Anakin, similar to Satine's relationship with Obi-Wan. Both leaders neither side with the Republic or the CIS and don't seem eager to be drawn into the war, but for entirely different reasons, since the welfare of their respective peoples rely on different philosophies. I'm actually surprised that Anakin has been able to keep his hatred for the Zygerrians relatively under control. The Queen's analogy about the Jedi being nothing but slaves to the Republic was very interesting, and may play into Anakin's eventual betrayal. I look forward to seeing how his relationship with the Queen develops in the next episode.
The action in this episode was pretty slow, but I was totally engaged in the plot and didn't mind that. Yet the scene with the Jedi and Rex facing off against the slavers in the arena was very fun to watch, especially since the Jedi were actually outmatched for once. Sure a Force-user can take care of one light-whip yielding foe, but an army of them was too much to handle. I'll also add that the animation in Obi-Wan's face and hair is continuing to get more and more realistic.
Another similarity between the Mandalore Plot and this episode was that they both depicted suicide. It's blatantly obvious that this show is not for young children. But this scene, as well as the deaths of innocent Togruta captives at the end of the episode, went a long way to setting a dark tone and illustrating the malevolence of the antagonists. I'm sure we are yet to see the worse in this regard, as a slave training camp was introduced at the end.
The cliff hanger ending of Slaves of the Republic with the heroes in peril was reminiscent of the Empire Strikes Back. It's great to see plot lines carry this heavily from episode to episode, rather than all of them being self contained. That makes the overall viewing experience better and builds anticipation for the "next chapter". In conclusion, I liked this episode better than the previous one, but still not as much as the Umbara arc. But I definitely feel that the series is continuing on an upward trajectory, and I will find it hard to wait till next year to see how this arc concludes.