We all selected guardian deities when we created our characters, but do we even know anything about them? I certainly don't know much about my chosen deity, Althyk, the Keeper.

What about adding a quest (or a series of quests) where you go on a pilgrimage (of sorts) to learn more about your deity and the lore associated with him/her? Rewards could include a unique ability related to your deity, religious artifacts (e.g. a special necklace with a pendant shaped like your deity's symbol that boosts stats or something), or something else. Perhaps at the end, you could personally encounter the deity and receive a blessing of some kind -- or even reject the deity and be prompted to change your affiliation.

This could be a great way to incorporate more lore into the game as well as some interesting locations such as temples, altars, sacred grounds, monasteries, etc. These could also be locations you could visit if you wanted to change to a different deity.