I am doing incremental backups on our database using rman.
Here is an example script that I am using :

replace script backup_db_level_1 {
execute script alloc_all_disks;
execute script set_maxcorrupt;
incremental level 1
skip inaccessible
tag backup_db_level_1
filesperset 6
format '/backup/df_t%t_s%s_p%p'
execute script rel_all_disks;
execute script archive_log_current;
execute script backup_al_all;

There are similar scripts for level 0 and level 2 backups.
In addition to this, I am planning on backing up (using os copy commands) password file and init.ora file.
What else is necessary for a proper database backup ?
Should I expilicitly backup control file too ?

Thanks a lot for your input