Change your terminal colour when SSH'ing, and change it back when done.

gistfile1.sh

#!/bin/sh

tabc() {
    NAME=$1; if [ -z "$NAME" ]; then NAME="Basic"; fi
    osascript -e "tell application \"Terminal\" to set current settings of front window to settings set \"$NAME\""
}

tabc SSH # switch to theme with name

/usr/bin/ssh "$@" # run ssh

tabc Monokai # switch to default theme