It's a [adjective] idea.
It's an utopian idea.
It's a miraculous idea.
It's a brilliant idea.
It's a marvelous idea.
It's a fabulous idea.
It's a wonderful idea.
It's a spectacular idea.
It's an amazing idea.
It's a beautiful idea.
It's a good idea.
It's a nice idea.
It's a great idea.
It's a swell idea.
It's a speculative idea.
It's an attractive idea.
It's a seductive idea.
It's a sexy idea.
It's a comforting idea.
It's a logical idea.
It's a horrible idea.
It's a noble idea.
It's a tentative idea. It might happen or it might not!