What defines a Function quantity?

I have a PDM15 in a race car. I have maxed out the functions at 200/200. are there specific things I can look for to try and eliminate unnecessary functions. like, most items are conditioned by the master switch(battery key) and the ignition switch being turned on. If those count as two functions per item. Would i be better off creating a condition of master and ignition combined and then putting that in my conditional functions. This would remove at least one used function from most to all of my functions?
Also do things like CAN inputs and outputs count as functions? would removing unnecessary CAN i/O help reduce my total function count?
Also do things like CAN inputs and outputs count as functions? would removing unnecessary CAN i/O help reduce my total function count?