dear hal,
i just read your two year old question about heschel and all the “wise things” your friends replied. i just felt that there is one thing i need to advise you: if you truly believe that no one should read just any jewish material before checking out it author, then heschel is not for you. and neither are all the jewish scholarly article that might interest you. what im saying is: when a person approaches a scholarly article, he must be open-minded enough to absorb the material so he can be able to decide if he agrees with the ideas or not. but with your attitude, there is no point in reading heschel, or buber, or even the rambams moreh, because you needa double check the idea with your ruv, if its oisgehalten! so why you bother reading them? people like you boggle my mind! trying to educate themselves but dont know how to due to religious anxiety.
anyways, back to your question, as far as im concerned there is nothing nontraditional in heschel’s writings that might upset even a conservative like you. he was a brilliant jewish scholar and he staunchly defends his faith against all his religious antagonists. i believe that his books have the power to inspire conservatives and liberals alike. i just finished reading his biography, and i was truly inspired by him. he was a great jewish thinker.