Ultimate might be a slight exaggeration, but regardless this is 20 films that I have lined up for you, Willem, to watch. Some of them I have seen and personally recommend. Some of them I'm just very interested to hear what you have to say about. I tried to be somewhat varied in my choices. There are no less than 9 films here that I gave 5 stars. I would've put Satantango and Jeanne Dielman, 23 Quai du Commerce, 1080 Bruxelles on here as well but I limited myeslf to two films longer than 180 minutes. Enjoy!
I added one film that wasn't in your library, Night On Earth, just because I saw several (four I think) Jarmusch films and I really like Night On Earth (which reminds me that I need to rewatch it soon). It can be traded for Stranger Than Paradise or Down By Law if you want though.