@Richy
No problem!
i think there is a select definition of art house amongst us, for me personally, art house is something that strays away from commercialism and i dont mean just because its a foreign film, its more to do with the artistic side of things, its like a painter selling a picture of a squiggly line for £10,000 and he calls it artistic, that translated into film is what i call arthouse, only god forgives is a mixture of arthouse i believe and some commercialism.
Although that is arthouse, I would say that that's more abstract film/experimental film (just one kind of arthouse film). If you look at the storytelling methods that arthouse directors like Ingmar Bergman, Robert Bresson, Federico Fellini, and many others you can see that they are much different than the classical narrative cinema of Hollywood (originated in the Old Hollywood of the 20's-40's).
David Bordwell has a great piece on "art" cinema as a mode of filmmaking that can be read here (for anyone interested in film criticism):
http://academic.uprm.edu/mleonard/theorydocs/readings/Bordwell.pdf
I agree with his points, but I would add that when defining "arthouse" cinema in terms of actual films being released rather than the inherent filmmaking mode one has to consider both marketing and financial success. A film like
Rashomon that was considered arthouse became a non-arthouse film when it was reformulated to fit the Hollywood model in
The Outrage.
Also, with the mentions of Quentin Tarantino here I would say that if
Pulp Fiction wasn't so successful, then it would be considered as an artistic attempt to mix low (exploitation films) and high (Godard) artforms in the cinema. Of course since it became popular now Tarantino is mainstream though.
Although in theory, "arthouse" should be applied to films based on their content, in reality a lot of films wouldn't be considered "arthouse" had they been made in the USA (more specifically in Hollywood).
Although I have stated my views on what should be considered "art" film and what should be considered "arthouse" cinema I will offer some my recommendations on the more abstract films that you describe:
Outer Space directed by Peter Tscherkassky
Dream Work directed by Peter Tscherkassky
Un Chien Andalou directed by Luis Buñuel
Diary Of A Pregnant Woman directed by Agnès Varda (this might not fully fit your definition but its definitely avant-garde)
The Cremaster Cycle directed by Matthew Barney (though this probably is better described as Video Art)
I also love the video artworks of Nam June Paik who is the pioneer of Video Art. I think that the lines between experimental film and video art are now blurring due to the fact that both films and video artworks are being presented in different ways apart from the traditional cinematic theater or traditional art gallery setting. Most of my favorite experimental films are short due to the fact that I don't have access to the features.
You may also be interested in the works of Andy Warhol and probably the most important figure in experimental cinema, Stan Brakhage. I'm also very interested in Shūji Terayama. There are many experimental film directors that I'm interested but unfortunately I haven't had the chance to see their works! I hope you get to explore this side of cinema more, and let me know what you think! Good luck on your film!