What are some good water mill cards for guardians?

I'm trying to make a Water Ciel mill deck but I'm not having great luck with it. For my mill package, I've got tidestone bovine, fractal of rain, and primordial ritual. But I feel like I need some more, because when I'm not able to mill and have to discard a card from hand to make an omen, it feels pretty bad. Anyone have any advice on what to add/remove?

The reason I want to try water Ciel is because of the new ally card which is a 0-1 taunter and when it dies, it becomes an omen, letting you gain more than 1 omen per turn. The other reason that water Ciel looked good is that water can slow down the game letting Ciel build up his omens, and even if I mill myself something I need, I can always turn it into an omen and play it with either Ciel's lineage release or that 1 regalia which swaps an omen for a card in your hand. I'm not very good at deck building though so I am a little stuck.

I tried looking at some stuff that nico runs since I figured she is also a guardian that likes to mill herself, but I'm not very familiar with Nico's game plan. The decks I see seem to go guo jia lvl 1 and use genbu to mill themselves as well as some other cards which are locked behind tamer class bonus before going Nico lvl 2. I could be wrong though, so any advice would be appreciated.