hello
Tablespace USERS is used because when DLP DB account is created no specific tablespace was assigned to this user so oracle used the default one. If you want to rename it you will have to assigned new tablespace to your DLP DB account and be sure that all previous element stored in USERS are available in it. But i am sure your DB team is aware of this.
The only DLP DB tablespace which is hard coded and name must not be change (or doing this very carefuuly as many other parameters will be impacted in DLP DB schema) is the one to store BLOBs (LOB_TABLESPACE) which contains messages/document.
regards