Positives:
+ The wandering samurai structure lends itself well to the episodic format. There is no overarching story, and each episode is self contained, so it can even be watched out of order after episode 1 with no loss of comprehension.
+ Grounded in a way that anime usually isn't. There are no pink haired lolis with magical swords or anything of the sort here, it's relatively realistic and restrained.
+ Artwork, music, costuming and character design are all very evocative of the setting and time period. It makes it feel like you're there. The OP is excellent and fits well thematically too.
+ Ran is a really fun character and makes for a great co-protagonist.
Negatives:
- On the other hand, Meow, the show's other co-protagonist, is punishingly annoying and nearly singlehandedly ruins the show. Meow's idiocy is so over the top that I actually started getting mad at her at points. The idea behind the odd couple pairing with her and Ran is good enough on paper, but she should have been dialed back 3 or 4 notches.
- Episodes tend to have highly formulaic setups, where Ran and Meow enter a city, get attacked by the townspeople who mistake them for villains, and then beg them for their help when they're defeated. At least half the episodes follow this pattern and it becomes a bit predictable and boring after you've seen a few.
- Action is overly sanitized. There is virtually no blood even though people are regularly getting killed with swords. It makes it difficult to tell when characters are dead or have merely been knocked out or disabled and undermines the drama in those scenes.
- Action choreography is hit or miss. Meow's martial arts look cool and well animated, but the swordfighting tends to be too "zoomed in" and it's hard to get a sense of what is happening or where people are in relation to other things.
- The drama is much weaker than the comedy, and serious scenes suffer for how closely they're juxtaposed with goofiness. In particular, the episode where Meow meets a childhood friend that has broken bad and started selling drugs is a huge swing and a miss for trying to hang a serious storyline on Meow, the goofball comic relief character of the series.
