Just to touch up on http://support.trakt.tv/forums/188762-general/suggestions/11258295-schedule-movie-refreshes and other things regarding the data refresh. Tbh I have seen little improvement regarding data quality on the site. Really sucks hard that any upcoming movie or newly airing show has a big chance of being "incomplete" or running with subpar artwork. There really needs an additional update job besides the update time on their respective source for the refresh.

(from the "new show calendar")
https://trakt.tv/shows/the-virtues only had a backdrop but posters uploaded over two weeks as well as two days ago
https://trakt.tv/shows/funniest-ever-tv-cock-ups also blank
https://trakt.tv/shows/love-beyond-frontier-2019 has had a non-English "English" poster since Nov 2018...
https://www.thetvdb.com/series/terrace-house-tokyo-2019 same

(stale artwork - at least the image there is gets grabbed at least the one time)
https://trakt.tv/movies/brightburn-2019
https://trakt.tv/movies/the-informer-2019

Also there is still no language fallback for artwork that isn't "English"... there are enough instances where the original language is sufficient for "English" too... and everything is better than blank images. I have been uploading images to the wrong language on TVDB for well over two years now just so that trakt grabs them (or whenever I last requested this)... really would love to stop doing this.

For a while now different developers or even individual users have been creating ginormous lists with thousands of items but with only three featured on each entry these tend to block everything out since they are also more likely to reach someone else that might throw them a like. Are there any plans to deal with this? Can we hide, re-categorize (non-personal) or downvote lists against this? Some of these serve no purpose other than actually bypassing advanced filters I'd argue or being pinned on kodi dashboards on dubious box setups I'd say...

Here are some examples of this:
https://trakt.tv/users/theultimatec0der/lists (one of his "all shows" has 50K items...)
https://trakt.tv/users/dborg/lists (I think his biggest is gone which was the thousands of "MOVIES NOT INTERESTED IN WATCHING)
https://trakt.tv/users/enormoz/lists
https://trakt.tv/users/zapras/lists/rarbg
https://trakt.tv/users/chas3down/lists/drunk
https://trakt.tv/users/fexi/lists/all-movies-with-german-audio
https://trakt.tv/users/opposite_lock/lists/15-18

Didn't find anything specific in the search but I was certain I saw mentions of this in the past too.

I love trakt. And I love TMDB. I contribute a lot to TMDB and think it is much better of a site and a community and more user friendly than TVDB. I understand that TVDB probably has a more comprehensive database for series compared to TMDB (I think TV shows are only a fairly recent addition to TMDB). However, contributing to TVDB is much more arduous than to TMDB, especially when it comes to getting incorrect data changed. The TVDB forum is fairly dead and slow to respond, me as a user have no idea if they keep track of our contributions.

Anyway, is there any reason why Trakt doesn't use episode information (especially air dates) from TMDB if they don't exist on it's respective entry on TVDB? Could this happen (any time soon- i.e. in the next couple of years)?

I have reported this issue before, and came across it again with movie:
https://trakt.tv/movies/the-mountain-between-us-2017

This movie on the Trakt web site did not show watched or collected. I know this to be wrong. I checked my local media data (in tinyMediaManager) and sure enough, it is both collected and watched. It also shows that it has already synced to Trakt with this data. This is proven in 2 ways. First, I do not manually mark anything watched in tMM. I mark when watched on Trakt and sync that to tMM. Second, it has the Trakt ID logged, which means that it has synced as that is how the Trakt ID gets populated. As a third method of verification, I have prior data backups from Trakt indicating that it was in fact collected and watched in Trakt in the past.

What steps are taken for data control and integrity? I have personally experienced two conditions where this issue could be happening. First is when there is a merge/deletion of a duplicate. I assume there is a merge process, or at least I hope so vs simply a removal of the duplicate. In this process, is there a pointer of sorts left in the system to where the former Trakt ID will point to the new ID? Second, Trakt has connection problems somewhat often. This happens usually around 06:00 UTC, typically +/- 2 hours. During this time, the site and service are up and down and not stable for a relatively short period of time, maybe 30 minutes if I had to guess. During this time, changes made tend to disappear and cause corrupt data. Corrupt data example is that a movie might appear on an list and it cannot be removed from it (this example has happened to me a few times). IF this is possibly due to maintenance on the site, server(s) or database, is anything done to prevent data writes during such times? Are there any checks to confirm data writes? For example, a write is sent to populate A, the database writes A and sends a reply that A was in fact written with success. Is there a transaction history that a user can review for changes under their account?

I do not know anything about Trakt on the backend, its database or programming. Due to this, I cannot really point to a problem and report it to be fixed. I can only identify that there is an issue and use my data management experience combined with my user experience on Trakt to identify possible problem areas. All I can be sure of is that there is with certainty an issue with data on the server side somewhere and it appears to be rare yet does happen. As a user, there is only so much I can do as access is limited and there is no way to know when data corrections happen exactly what code is used to execute the DB transactions. I hope I have provided enough where someone can review appropriately.

I don't do regular housekeeping of my trakt data and things are prone to get messy due to various bugs in apps and plugins but I'll always end up with duplicate plays at some point. Many of those end up going from check-ins to plays at the same timestamp which shouldn't get accepted as valid by the site at all imho or at least end up getting merged. Despite not not being advertised outside of some support threads and a single kodi forum thread I end up getting a lot of visitors on my duplicate removal script (500+ last year) which tells me this is quite a common issue and affects plenty of people :/...

Personally in an ideal view i'd have just a single line per show with in-line tick to confirm if a show has been marked collected!

The calendar has been improved greatly of the years, thank you, I currently have it set as basic as possible with a grid with no pictures and filtered to only display my shows in progress.

I'd love to take this further, and be able to have a ultra simple text-only at-a-glance calendar view of multiple 4-5 weeks at once, where i could scroll through the weeks vertically like a calendar app.

The Settings page could have an option for the Basic calendar which would have a Smaller font size on the calendar to fit more in on the page, with maybe an option for 1 or 2 lines per show.

Via the calendar settings you could add tick boxes in the same vein as the current one for "Hide Specials" for the calendar items of: Time, Channel, Watched, Collected, Hide this show, Lists, rating etc. So that the calendar only displayed the things that were important to the user.

These hidden items could be displayed in an expanded box like that of the (clock+ icon) on the right of the watched/collected boxes on episode or movie home pages.