Would the writings of the Bahá’u’lláh qualify?
I've read them, and I don't think so, same with the Maitriya. That's why I believe they emphasize on spiritual element of them rather then eloquence. For example, the Bab would emphasize on his words being signs to the heart of sincere believers, but Quran, challenges disbelievers and believers alike to think of it's content as a miracle in itself and that they can try to bring the like of it.
To say "spiritual signs" - that's subjective, and that is a flaw of Bab and Baha'allah, they emphasized too much flowery spirituality being the basis of their miracle, but that is too subjective.