Wow! Into the Valley of Death is a dream come true! Frankly, so are the WWI German Cavalry sets, such as Uhlans and Hussars and others. Here is an idea for supplementing all of these Crimean and WWI Cavalry sets.
Below is a link to a LW/EVO set of WWI German Cavalry with a casualty prone horse pose as well as a dead Trooper and a kneeling-shooting from behind horse Trooper poses.
This set was produced in both Terracotta (Brick-Red) and Silver. The link shows Silver. Because I'm not a painter, and love colors, I have both. The Terracotta works just fine, thank you, for the Crimean War and the Silver does too with WWI German Cavalries in Gray color.
The horse works great as is. Simple head-swopping with the dead or kneeling-shooting Troopers works equally simply too. Link compliments of PSR:
Sure, anythings possible with conversions. If you like the Esci Polish Lancers, you could put their unique heads on the 17th torsos and use the falling horses and/or the LW/EVO prone horse and rider to make some casualty conversions. A little paint and voila!
The new "Into the Valley of Death" set opens up lots of new possiblilities for foot Cavalry Casualties too.
Hopefully someday S*R or HaT will make new Polish Lancers. They certainly deserve to be immortalized better in plastic. But if HaT does it first, they'll never make casualties. Their recent forum polls indicated Napoleonic collectors didn't want casualties so, you'll have to make conversions if you want any. And remember, my point here is to make Cavalry Casualty conversions, not whole armies.
Airfix already has casualty horses and downed riders in their French Cuirassier (light blue) and British Hussars (red) sets that could maybe be used with S*R's. Even Airfix's recent re-release of U.S. Cavalry in a nice mid-blue has the best downed horse which has already made it into my S*R Cuirassier stable. The U.S. Cav horse has very simple accoutrements, so it lends well to adding more Napoleonic saddlery.