You could create a script /usr/bin/dispatch that contains #!/bin/sh file=`env PATH=$THIS_ARCHITECURES_PREFERRED_PATH /usr/bin/which $1` shift; exit

You could create a script /usr/bin/dispatch that contains #!/bin/sh file=`env PATH=$THIS_ARCHITECURES_PREFERRED_PATH /usr/bin/which $1` shift; exit "$file" "$@" for each machine to use in your scripts. Tuning the path becomes a once per architecture, rather than once per script, task.