Essah's Czech Resources
I've been studying Czech for a while, and I compiled a list of the best resources for learning Czech. I'm aware that Nueby also made a short list and that there's some overlap but I also have some additional resources. It is by no means exhaustive or all inclusive list, but rather my picks for the most useful sources, while avoiding 10 year old forum posts with 70% dead links. (yep, came across those too).
I hope it will be useful for someone. Feel free to suggest other resources in the replies if you want, and I'll consider adding them to the list. (I'll add more myself if I find some)
Here's another resource which I really like. I don't think you mentioned it. It's called "The Valency Lexicon of Czech Verbs with Complex Syntactic-Semantic Annotation". If you're ever wondering what the valency of a verb is, you can find it here. It basically shows a verbs arguments and their cases. There's also a lot of other information relating to this. Very interesting if you like grammar!
Vallex 3.0: http://ufal.mff.cuni.cz/vallex/3.0/
Great compilation of resources! I wholeheartedly recommend Stream.cz - I believe you do include it in your list but only as a site to watch Krteček. It offers a great variety of original shows in Czech with closed captions - IMO the best source of videos for a semi-advanced learner, who can't watch regular videos and yet they want to improve their listening skills and vocabulary!
For example: Slavné dny (Famous Days) - short documentaries. https://www.stream.cz/porady/slavnedny
It requires not only a high level of Czech but also knowing the Czech political scene in the last few years, so nothing for a foreigner. However, for an expat who has read the newspaper regularly in the past year, it may be just what they need to reach that C1 and have fun while they're at it. :D
I'd like to add that Stream.cz also has a international Youtube channel, where they partly dub some of their videos in English and put English subtites. They even make videos about Czech Republic in English! https://www.youtube.com/channel/UCt7oj318jVQi7vRbc1bNjJA