Oh man... I wish I had some good titles to suggest, but the majority of the manga I read is action/adventure, fantasy, and a lot of cutesy, fluffy shoujo stuff (for some reason, I've never quite gotten over my love of
Cardcaptor Sakura... XD).
I am a
Detective Conan addict, though, and Clue is possibly my favorite board game in existence... so I'll have to check out your suggested titles this summer and see if I can discover some favorites of my own. I haven't read any new manga in a while, so I've been dithering on what to start next.