The Smarta answer to 'who is greatest' is to refuse the question. In Panchayatana worship five icons — Ganesha, Shiva, the Goddess, Vishnu and the Sun — are arranged as a quincunx, with the deity the worshipper prefers at the centre and the others around it; South Indian Smartas add Kartikeya to make six. All are held to be forms of the one Brahman with attributes, and the personal deity is a stage on the way to the Brahman without them. Tradition ascribes the arrangement to Adi Shankara in the eighth century, but archaeological sets from Nand are dated to the Kushan period, long before him. Pattanaik's gloss that Purusha is personified as the three gods and Prakriti as their three consorts is his own.
Base telling of this frame; no god is placed above another, which is itself the sectarian position.
Smarta tradition — Wikipedia; Panchayatana puja — Wikipedia; Trimurti — Wikipedia
Sources: Smarta tradition — Wikipedia; Panchayatana puja — Wikipedia; Trimurti — Wikipedia
Vishnu meditates in the Himalaya while Lakshmi shelters him as a badri tree; the sages Nara and Narayana choose the site; Shankara recovers the image from the hot spring.
Shiva and Parvati must choose between their two sons.
Parvati wants a guard of her own and shapes a boy from the paste on her body.
Ravana wins Shiva's own linga by fierce penance, to take home to Lanka.
Parvati asks Shiva for the secret of never dying.
The Maitri Upanishad names Brahma, Rudra and Vishnu together as portions of one being, matched to the three gunas.
The sage Atri and his wife Anasuya earn great merit through their conduct and austerity.
Vishnu and Shiva are shown as one figure divided down the middle.