Usually, pg_basebackup can be called directly if we are using an identical filesystem layout on the target system. If this is not the case, pg_basebackup allows you to map the master's filesystem layout to the desired layout:
-T, --tablespace-mapping=OLDDIR=NEWDIR
relocate tablespace in OLDDIR to NEWDIR
If your system is small, it could be a good idea to keep everything in one tablespace.
This holds true if I/O is not the problem (maybe because you are only managing a few gigabytes of data).