I'm not really familiar with German folklore, nor Asian/Japanese pantheons, so I'm not spealing for Ulms, Tien C'his nor Yomis
I think that Wyrm should be restricted for Skandinavian nations (Helheim, Vanheim, Midgårds) of all ages and UW nations (they have few enough pretenders already), basing on the myth of Jormungård.
(besides, most of the skandi-nations are actually bless nations who'll probably use some other pretender
)
Cyclops - probably Arco all ages?
Titan - This pretty all around. Almost all pantheons have a thunder god. Thor is in skandinavia, This guy just spells Zeus for Arcospehale, ..etc. Perhaps just disallow it form Agartha, Abyssia and other nations that really won't revere a thunder god?
Phoenix - Has anyone any clue from where the orginal Phoenix myth is from? It should be themtatical for all fire nations anyways.
Prince of Death could probably use more restricting for balance reasons, althought all Pantheons have a God of Death in some form. It's just so freakishly undercosted.