use a different algorithm for "Highest Rated" stars and directors
My "Highest Rated" stars list is filled with stunt people and costumed little persons. My "Highest Rated" directors list is heavy with animators from yesteryear, most of whose works I've never seen.
With all due respect to the above persons, most of them have made these lists because I've given one or two high ratings to a specific work or two, but ~not~ to their collected ~body~ of works — leaving my list rather uninformative for my liking.
I realize you also have a "Most Watched" setting — but then I'm just left with Tom Hanks and Steven Spielberg — who are probably close to being ~everyone's~ "Most Watched" [and they certainly aren't my favorites].
Might the "Highest Rated" be measured in a way where the stars and directors are weighed by our interest in their ~collective~ works? For example, if you give "Fantastia" 5 stars — but it's the only film you've seen from that creator's exhaustive list of films — he won't appear as your "Highest Rated" director?
I certainly prefer P.T. Anderson to Ben Sharpsteen[?], and I certainly prefer Ryan Gosling to June Christopher[?], but these lists give no reflection to that.
We do have a manual way of removing "cameo" actions from stats if they are reported as such (email email@example.com).
We’re looking at improving our heuristic that identifies lesser roles in a film’s cast as well.
Personally I would like it if voice roles were completely separated from normal roles, but I suspect that those who appreciate animation more than I do wouldn't like this idea.
I can't edit my prior post, so I'll just post this. I meant to say "2/11 with >1000 views" in regards to Miloš Forman, not 4/11.
I agree with OP's sentiments in regards to the actors category. Many of my most viewed actors are voice actors with little to no role in the movie. For example, I apparently have seen 52 movies with Frank Welker (almost twice as many as any other actor), and I looked up his role in a few of them. In Frozen, (2013) he is credited as "Animal Vocal Sounds (voice)", and in most of his other movies he has similarly minor roles (and often even "uncredited" on IMDb). I wouldn't have any problem with him showing up in my most watched actors list if he was in the top 20 (not sure of this number exactly) billed actors of all these movies. I'm not so sure I would go so far as to say he (and other like him) should be removed from the letterboxd pages for the movies they have such minor roles in, but I do think that there should be a cutoff in billing position for an actor's role to contribute to your "most watched"/"highest rated" actors list. This may be an overly simplistic/harsh solution, but I suspect that anything more complex/accurate would unfortunately be very hard to implement.
I also think that the "highest rated" actors list in general rather inaccurate (at least for me), but I can't think of any good way to change this, since the data is based on our movie ratings which may have nothing to do with whether or not we like an actor in that movie.
As for directors, I think there is absolutely nothing wrong with the "Most Viewed" lists. However I think a cutoff of 2 watched movies for the "Highest Rated" list may be too low. When inspecting my highest rated directors list, simply removing all the directors I had only seen 2 movies from made the list much more accurate to my tastes. If a working director only has 2 or 3 movies (with over 1000 views or so), then in this case if might be okay to keep them in the highest rated list. For example, I can't really complain about Paul King (seen 2/3 with >1000 views) being in my highest rated list, but I'm not so sure Miloš Forman (seen 4/11 with >1000 views) should be there. Otherwise increasing the floor to 3 watched movies seems reasonable to me.