As you mention the importance of lounge access, you need to hit Gold. BD used to be easy-ish to achieve Gold, but with the forthcoming LH takeover that will probably go. BD has been full at times of fair-weather friends who were only there for easy Gold, and in discussions about jumping ship on the BD forum mention is often made of AC, OZ and TK for their relative ease of attaining Gold. Of course, they all may have other issues, so check their programmes carefully for what suits you!