Health, you seem to have missed an important nekudah of the mashul. You are correct that the bal agala is the main actor, but the horse and wagon are necessary and should also be shown “appreciation” in the form of care and maintenance. Horeses especially are living creatures with enough intelligence to understand extra care, a kind word and a pat on the neck. Soldiers deserve at least as much appreciation as one would give a faithful horse.
Another Item. Without disputing the issue, I take exception to the use of the term “yeharog v’al ya’avor” applied to issurim simply as an exclamation point. Yeharog v’al ya’avor is reserved for the most severe issurim, I.E. the Big Three (or any issurim b’shas hashmad). To apply the term to other issurim which, while serious, don’t really rise to the level of ultimate sacrifice does not so much reinforce the severity of the infraction as it deminishes the value of of that sacrifice. I am ready to lay down my life rather than allow myself to be forced to cross myself, or kill a fellow Jew (such cases actually happened in the Shoah), or commit incest. Should I really be ready to do the same to avoid hearing a woman sing, or use the internet, etc.?
P.S. Shoah is easier to type that holocaust.