The third and final season of "This Country" whilst still very good does, I think, show it's the right decision to end the series now, whilst still on a high, rather than run it into the ground.
Arriving back in the village we learn the sad news that "Slugs" has passed away, Kerry (Daisy May Cooper) and Kurtan (Lee Cooper) deal with that, and later the death of Kurtan's half-brother. Kerry's Dad returns to the village and his arrival has some unexpected outcomes for her. The Vicar (Paul Chahidi) comes to appreciate that some of the parishioners take advantage of him and begins to wonder if a new challenge might be required.
The sad passing of the Cooper's real-life friend Michael Sleggs, soon before filming was due to start is dealt with in some poignant rewrites to the season, particularly the first episode. There is a general feeling of increased pathos across this run, partially as it was announced that this would be the end of the show and also in the plot ruminating on death and moving on quite a lot. One of those episodes, the fourth, which combines Kurtan trying to find some meaning in the life of his half-brother with Kerry and later Mandy joining the Parish book club is one of the funniest in the entire series. That said, on the whole I'm not sure that the third season consistently reaches the heights of the second and the finale, whilst appropriate I found a touch underwhelming.
But, given that the setting is supposed to be a small village where nothing happens, the capacity for fresh stories is limited, so like many sitcoms, they've made what I think is the right decision to go out whilst the show is still fresh and interesting.