It seems to me that nahel-bond level spren that we've observed seem to fit on a *spectrum* from honour to cultivation. For example honourspren being very clearly very close to honour, and wyndle clearly being very close to cultivation, but the other types we're aware of (highspren, ivory, etc) not clearly belonging to either shard's intent.
Why wouldnt the three god spren follow a similar pattern? Stormfather pretty much pure honour, the Nightwatcher pretty much pure cultivation, and say cusicesh representing a point where their magics and intents were balanced equally? Some kind of in-between godspren?