Plus I can make a FEW arguments for a FEW of the "sub gods".
Arthur: Been over this one too much. With Excalibur he is DEFINITELY god tier.
Achilles: He, like Arthur, has divine equipment. Armor and shield forged by vulcan, and spear forged by his trainer Chiron, the same person who trained hercules. Being dipped in the river Styx made him durable to the point smite states the gods fear a man they can't harm, meaning his durability is likely higher than most gods power outputs. Plus even in myth he never used his full power as he often fought basic humans and was often cocky. And look at other demigods, Hercules, Erlang Shen, and even Rama are capable of god tier power. Speaking of Rama...
Rama: He, like a certain dwarf, is the avatar of Vishnu. But he also weilds the infamous Brahamastra, a set of arrows summoned via a chant, shown in his game as his astral arrows. These weapons were not only capable of wiping out the universe if the user so wanted, but where the one thing needed to KILL Ravana in mythology. Speaking of Ravana....
Ravana, his brother, and Bakasura: In hindu mythology demons often were as powerful as various gods. Ravana ESPECIALLY so as well as his brother. Bakasura also fought a man who was basically hindu hercules. Looking at mythology for some context, that man fought Indra. Indra being the equivalent ot Zeus in hindu myth and the bother of Agni. And Ravana was blessed by Shiva, a definite high tier as he and his trio are the ones in hindu myth responsible for the creation, destruction, and maintenance of the universe, with invulnerability against divine and demonic beings.
Erlang Shen: demi-god infamous for his defeat of Sun Wukong, and should scale to the monkey king.
Kuzenbo: while idk if this is the case in smite, often the difference between a Yokai and a Kami, gods, were their relationship and disposition to mortals. Kappa were known full well for riding both sides of that line, and Kuzenbo is their king.
Cerberus: story and lore feats definitely put him in that god tier range.
Hercules: has both wrestled and fought Hades on several occasions as well as his fight with Cerberus.
Cu Chulainn: Clashed with The Morrigan and defeated her in his lore. And she is THREE goddesses in one body.
Also we should WAIT to rank "sub gods" to some extent as we don't know the full effects of what Persephone did to Yggdrasil and her plan was to swap things around for gods and mortals. Plus with MULAN coming out, and Baba Yaga, we dont know if she is just a witch or if the goddess version of her is used, things may not be so simple.