Other reviews have noted how Kenobi reads like a Star Wars meets Firefly crossbreed, and I agree- but that doesn't make it any less enjoyable. In fact, it adds a extra dose of flavor to a universe gone stale. It also adds spice to the story that the hero of this eponymous tale is largely viewed through the eyes of others and judged by them on his actions.
Another welcome dash of spice comes when we're treated to a dose of romance, something never really explored in Obi-wan's extensive and colorful history. Author John Jackson Miller clearly wasn't awed by any sacred cows and treated Obi-wan as a person, not a mythic figure, and did him justice.
Plotwise there's nothing to add that other reviews haven't already covered, so my two cents is that Kenobi gives Star Wars fans something they've long awaited: a look at Obi-wan's life while biding his time on that backwater planet. Not everyone will like or agree with what author John Jackson Miller gives you, but I'm sure you'll be intrigued by it.