I'll tell you what we did. We kept the standard auto tip the way it was. We know this is a dollar figure you can not get out of paying PLUS with the percentages split being such a small minute amount each person gets, it is not worth the extra work to do it.
Our cabin steward, we tipped him in cash a few bucks each day then "after hours" when we caught him on another deck working on the Lido deck on the last day. We also tipped in cash our dining room waiter on our last night of dinner.