I was sketching out some Brickonicle doodles (I hesitate to call it “art”) while listening to the podcast (more-or-less caught up now), and I heard about basing Ta-Koro off of medieval castle, which it gave me some inspiration for its “religious” traditions.
It seems to me that, even if all the Matoran share the same religious beliefs, their customs and manner of worship would vary greatly.
Following the medieval and elemental themes I’d imagine that the religious traditions of Ta-Koro would be very Patron based, and heavily involve candles.
By “patron,” I mean that each Ta-Matoran could take a hero from the past as a role-model and a sort of “spiritual guide.” I’d imagine that there would be little shrines to these “patrons” set up in homes and all around the village/city, each with candles and an image of the hero.
The idea I had was that for the Ta-Matoran, a candle-flame represents a prayer, and keeping that flame lit is an important of getting your prayer answered.
I also think that the Ta-Matoran could distinguish themselves by using icons (stylized holy images) instead of statuary (I know they are more Byzantine than Feudal, but they’re from the right time-period). I think classical marble statuary would be more a Le-Koro thing.
(Note, I’m new to the message boards and this is my first topic, feel free to give me any advice you have for making points more effectively in the future 
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(Edit, more images! 
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