And sometimes, dreams may become a movie.

Could it be Wizards?

Wizards
http://www.imdb.com/title/tt0076929

It's not Ralph Bakshi no. My recollections aren't nearly weird enough :P

Kinda sounds Fritz the Cat movie?? My best guess.

Thanks for the tip, I forgot that I wanted to look for this movie someday and thanks to yourself and youtube I finally found it now.

Castle in the Sky
http://www.imdb.com/title/tt0092067/

Who Framed Roger Rabbit?
http://www.imdb.com/title/tt0096438/

No on both counts :P Almost certain it wasn't anime, and the love interest wasn't Jessica rabbit.

Have you used IMDB's advanced search function?

Vaguely sounds like Heavy Metal, though that one didn't have pirates...

I'm giving it a try now, but I don't think that I have enough to go on sadly. What I have tried is going through lists of animated films by country. I still want to look at France, Germany, Italy and Russia. Unfortunately there are loads of animated films. The one that I have found that is the closest to what I remember I linked in an edit of my first post.
I'm going to find that damn film if it kills me!

Fire & Ice maybe? Though I don't think the animation matches.

http://www.imdb.com/title/tt0085542/

Much love for Heavy Metal! Not that though
No realistic looking characters no. It was far more cartoony, like the movie I linked in an edit of my first post.

It was years ago but I got help on one of IMDBs forums, I think it even was dedicated to finding old films with far less information. I remember thinking those guys was amazing.
So I'd go look at IMDBs forums, not the film specific ones for help.

Thanks for the hint :) I'll check it out and report back if I find anything