Definitely Github, Bitbucket or something similar. Easy to use for everyone. And if someone found a bug or anything, then submitting patch is easy as hell.
^ These are words of wisdom. Sourceforge is very inaccessible in comparison. It's so bad that I'd actually encourage you to move it to github, if you want to keep working on it.
Having never hosted anything before this on either, I really didn't know. That said why is SourceForge so difficult to use? Seemed pretty straightforward for me to set up and host the files. It has a small forums, a Wiki if it ever became necessary. I don't really need much else do I?