Great points you have there. I'll try to talk about them in relation to my deck.
The good thing about Physalia is that even if they are removed from the field the damage remains. However, I could see removing one, maybe a second for more control.
Congeal wouldn't play too vital a role and the deck might be quanta strained if I added squids, so adding a couple would probably help quite a bit.
As for Ulitharids, the amount of them in there is mostly because they can be so helpful in the early game. In more recent games however they're not needed until mind-game, and so I think removing one is safe.
Lycans are great in this deck, and I'm not too concerned about keeping the theme absolute in exchange for power. Using them in place of machines has done very well for me in testing.
Thanks for all the comments everyone