It really isn't the idea, but the execution that's essential.
There have been lots of ideas, which i thought were stupid and too simple to be profitable at that time. But i've seen them grow really popular and profitable.
So i guess you should find someone to work with you on those ideas, and hope for the best. It may turn out that some those ideas become successful, but there's a higher chance that none of them do.
Discuss those ideas on HN, and i'm sure you'll get lots of useful feedback.