Do I need to replicate every piece of data across each record?

Please note that this is a non exhaustive list: if you are going to use filters, facet filters, optional filters, or rules (to pin, boost/bury, etc), or rank by specific attributes, you should replicate each attribute in each record. In other words, each record should have the same set of attributes. Otherwise, you will run into unpredictable issues because Algolia does not support filtering by null or filtering by missing attributes.