"ripe thoughts" is correct and usable in written English.
It is an idiomatic expression and is used to talk about ideas that are well-developed or mature. Example: After years of contemplation, I finally had some ripe thoughts on the subject of happiness.
It's clever, it's ripe with thought, it's ugly.
Here is a dreadfully ripe and pessimistic thought: Did the chimps become infected by a dose of concentrated mankind?
Life-size, the subject turns his head upward on his sinewy neck with a hooded gaze that seems mildly interested, slightly supercilious, and ripe with a thought that is an instant short of being spoken.
My immediate thought: a ripe yet lean sauvignon blanc, with acidity present and accounted for, as in a juicy apple.
It may well naturally mean that food is present, but salivation is not a thought or thought content and it is not ripe for false semantic tokening.
However, as he examined the servers, he noticed Spam levels were dropping precipitously – down 30% over the last year at least – and the thought the time might be ripe to pull the plug.
In an essay on the firm's new site, McGlade delves deeper into his thoughts as to why these industries are ripe for innovation.
According to Duncan-Jones, "the speaker claims to be unable to voice his thoughts of love; they are ready for utterance (ripe), but remain buried (in-hearsed) in his brain because he is intimidated by his rival".
A result is that a part of the country where energy supplies were long thought to be largely tapped out is suddenly ripe for gas prospecting.
However, murder most foul is more often local and banal, or a crime of passion, and beyond that, murderous thoughts are as much fuel for song as the act itself, making these also ripe for song suggestions.
