Blues.Gr is about Blues in Greece. So members of Blues.Gr should be native greek speakers in their majority. Nevertheless, people from all over the world might be interested in Blues.Gr so English should be considered as a language to be supported in Blues.Gr.
So what I propose as far as language is concerened is:

• Let's keep navigation and content that can be internationaly interesting to English.
• Greek is allowed all around the site. But let's use Greek with greek characters. Let's avoid Greeklish.