I do have a degree of syncreticism, though it's largely in terms of which Gods I'll reference when talking about certain concepts. Though that's largely because 1. we know precious little about the vast majority of the attested Gods in pre-Christian Germanic polytheism (and sometimes nothing whatsoever about them besides a name with indeterminate etymology), and 2. Western culture at large is, I think, more familiar on the whole with Greek Lore than Germanic Lore.
Well, that and the customized Lore I'm crafting does take a lot of inspiration from other sources(which I'm totally okay with doing because, hey, if Christianity could take our stuff, I can take theirs ^_^). For example, I'm crafting a whole thing with "Tiu", another English variant name of Tiwaz/Tiw/Tyr, with the starting point for my inspiration being, of all things, Dante's Divine Comedy. The reason for that is because modern vernacular tends to use "God" in vague reference to the Sky, and in any case, it's highly likely that the word "God" came to replace "Tiw" as the English word for the same concept. Tiwaz/Tiw/Tyr wasn't just the name of the Sky King God Himself, but like the Greco-Latin cognates Theo(Zeus?)/Deus, also was the word for "God" as a reference to the type of being involved. (The Website "Norse Mythology For Smart People" cites Hangatyr, which means "Hanged God", one of Odin's names). All that said, the Divine Comedy is just a starting point; the actual concepts represented in the various cosmic "levels" I'm crafting have nothing to do with general good behavior, but rather deals with the journey from cowardice, to courage, and finally victory, which is what this God is all about. (Well, that, and I'm using the more standard "seven" levels per layer rather than nine).
I'll probably adapt other concepts from general European Christian and pan-Indo-European Lore when crafting aspects for other Gods that have been lost, as well. We don't really have perfect analogues for Aphrodite, Athena, or Artemis, for one thing. (Though Freya is kind of what would happen if Aphrodite and Athena had a love-child ^_^).
And with ALL of that said... I have no idea how to answer this poll. LOL