In the Couchbase 104 training series, several key topics are addressed through a Q&A format, focusing on the use of views and indexing in Couchbase. The discussion includes the limitations of wildcard usage in view queries, suggesting range queries as partial substitutes, and the complexity of modeling graphs with views, particularly when considering the depth of relationships, for which a combination of Couchbase with graph databases like Neo4J is recommended. The text also explains that altering the default order of collation requires source modification, as Unicode collation is preferred, and highlights that grouping by month using dateToArray() is challenging without adjusting the indexed key. It further clarifies that multiple emits in a single map() function contribute to a single index, facilitating simulated joins. Finally, the inability of views to perform full-text searches is noted, with Elastic Search integration and the N1QL Couchbase Query Language mentioned as alternatives for ad-hoc queries.