La Marseillaise is very bloody and militaristic because it's a war song, France was at war against Austria at that time -1792. Its original title was "Chant de guerre pour l'armée du Rhin" (War Song for the Army of the Rhine). The song was published in Marseilles under the title "Chant de guerre pour l'armée aux frontières" and a regiment walked from Marseilles to Paris enlisting new soldiers on the way and singing the song, hence the name La Marseillaise.
New Zealand born singer Graeme Allwright wrote new lyrics (one verse)

La Marseillaise De Graeme Allwright et Sylvie Dien

Pour tous les enfants de la terre
Chantons amour et liberté.
Contre toutes les haines et les guerres
L'étendard d'espoir est levé
L'étendard de justice et de paix.
Rassemblons nos forces, notre courage
Pour vaincre la misère et la peur
Que règnent au fond de nos cœurs
L'amitié la joie et le partage.
La flamme qui nous éclaire,
Traverse les frontières
Partons, partons, amis, solidaires
Marchons vers la lumière.

Graeme Allwright, Sylvie Dien
Texte libre de droit, offert par les auteurs, à distribuer sans modération.

For all the children of the earth
Let's sing love and liberty
Against all the hatreds and wars,
The standard of hope is raised,
The standard of justice and peace (is raised).
Let's gather our forces, our courage
To vanquish poverty and fear
Let friendship, joy and sharing
Reign at the bottom of our hearts.
The flame that lights/enlightens us (can be both meanings)
Crosses over/through borders.
Let's go, let's go, friends, in solidarity/united,
Let's go towards the light.

Btw, I don't know if it's just me but "the fearsome/fierce soldiers coming to cut the throats of our sons, our consorts" "the impure blood watering our furrows" meant nothing to me, it had no reality, it was just words. I never developed an urge to kill people around either.