True low-hanging fruit, good for a first-time contributor:
There are a lot of classes without meaningful toString() implementations. Some of these would be very nice to have for investigating bug reports.
Some good places to start:
- CQL3 statements (UpdateStatement, DeleteStatement, etc), QueryOptions, and Restrictions
Some packages not to worry about:
- Deep internals that don't already have them (org.apache.cassandra.db.rows/partitions/etc)