Should the Redo log on a production MySQL server be configured to another location?
Yes, that would be a good idea. I have mentioned a FaceBook Engineer's Blog about doing that, along with putting the DoubleWrite Buffer and Tablespace Files in other places, in my other posts

Feb 24, 2012 : Tuning dedicated Percona Server with XtraDB for OLTP (Also See Switching Gears TO RAID)
Feb 06, 2014 : MySQL on SSD - what are the disadvantages?
Jan 27, 2015 : what would be the primary disadvantages of splitting my tables into table spaces and/or separate schemata

RAID5 ??? OMG, NO !!!!!
Please do not put anything InnoDB-related in RAID5

Feb 14, 2012 : Is raid 5 suitable for a mysql installation?
Mar 24, 2013 : Innodb table is taking randomly long time to execute the insert query and in show processlist showing as queryend/updating

Since you will need the the redo logs only in the event of crash recovery, I would go with RAID10 SAS Drives for the redo logs because they are sequentially written files. I would shy away from RAID1 because you want full redundancy of disk in the event of a disk crash. RAID5 does plenty of parity checking which can inhibit sequential writes.