I can see the appeal, but I have my doubts as well.

The Eastern front was more dynamic on a large scale, if just as brutal.

To do the Western front, it would be best to concentrate on a portion of it, such as The Somme: Total War. But somehow even that would fail to capture the flavor of a battle where over a period of 5-months the casualty rate worked out to almost 5 men every second. And you would also need to be a brigadier general rather than the prime minister.

Cavalry were used, even on the Western front, where the idea was that infantry would create breaks in the German lines which the cavalry would then exploit. It never worked very well, and the horses tended to get hit by German artillery as they sat waiting massed behind the front line, so they stopped doing it eventually.

Artillery played such a large part in the conflict, especially after the British developed the creeping barrage, that it would need to be modeled somehow, but by this point the range of the guns far exceeds the size of a Total War map.