I just read a G.K. Chesterton Father Brown collection for the first time: The Innocence of Father Brown. I was anticipating enjoying it, but I didn't. I mean, they were entertaining enough to keep me occupied for most of a sick day drifting in and out of consciousness, but really I was disappointed.
From a plot perspective, there is a crisis in fiction's requisite suspension of belief: the stories simply cannot all be true. For example, the initially thief, later comrade to Fr. Brown, Flambeau, shows up as the crook in way too many for it to be surprising that Fr. Brown figured him out ... again (Did you not recognize him? What is going on here?). For an innocuous country priest, he shows up in way too many random locations (unless he is really an absentee bishop); his own village is frustratingly undefined and between the stories there are just too many odd people, rich and suspect types around to be likely.
From a character perspective, Fr. Brown is a bit flat and frankly just a little bit annoying probably because he is not amusing (or rarely so); he's just a little bit too 'intuitive' for me: in quotations because often intuitive turns out to be "oh yes, I also happened to read the will which says X, which is the answer." Hmmm, very clever of you, Fr. Brown. He (both Fr. Brown and Chesterton) also plays all of his cards close to his chest -- usually in mysteries you expect to have to guess just one or maybe two random pieces of information to get the game.
So, Fr. Brown is more in the Sherlock Holmes type of loner genius, but he doesn't have any problems and he doesn't have a mysterious past, he's just apparently heard the detailed (meaning exactly how I did it) confessions of every type of criminal, and he is pure, and very philosophic (also kind of obnoxious to me).
In other words, the books are a bit tedious because they present Chesterton's almost apologetic for his take on the Catholic worldview versus the rest. He seems to have been more interested in making points about priests (being "cloistered and pious" doesn't mean they don't know the ways of the world; in fact they know the ways of man more intimately than anyone else because that is their "profession"), in general the Catholic Church's teachings (confession of sins is simultaneously both freedom and a sufficient penance; Catholicism is the worldview of reason; the fundamental thing that must be seen about mankind is that we must look inside and admit that everything is not alright, the church's approach to sin and sinners - confession - gets many more and better results than that of society, etc.), skewering various groups in society for their incompetence, destructiveness, insufficience (socialists, new pagans, English evangelicals, teetotallers, calvinists, etc.), or making a sort of broad moralizing point: as man lives in sin his sins get smaller and smaller (meaning I think more and more personal), and meaner and meaner (meaning more and more vicious).
Through each of his stories he gets across fairly bluntly a related point on one or several of these. Now, I grant this is a point I usually find interesting and most always agree with. What I object to is use of the genre, which caught me by surprise. Perhaps if I pick up a Father Brown collection again, my approach would be to try to read them as Platonic dialogues. The plot is not exactly an accidental happenstance to the philosophy therein, but it is definitely subservient to the point being made, though in the best dialogues the plot is itself also that point. It is as though Chesterton formulated a moral truth to himself and thought, 'now how can I get a Fr. Brown case to exemplify this?' Thus, in their own way these tales are enjoyable, but don't expect the literary delights of Dorothy Sayers.