Normaly you would only collect system statistics once. Of course, if your system changes drasticaly, for example if you upgrade it with faster CPUs or faster disks, then you would normaly recollect them. But there is certanly no need to recollect them repeatedly every day.

You would store those statistics in a dedicated table, created by DBMS_STATS.CREATE_STAT_TABLE procedure.

Now you only need to flip-flop the OLTP/batch system statistics from that table into the dictionary by using DBMS_STATS.IMPORT_SYSTEM_STATS procedure at the desired intervals.