Stucco gone bad in the snow on tight radius walls

I have a two story half round turret that has stucco on it, as well as a qurter round with the same problem, both are about a 7′ radius. This home is in the California mountain range called the Sierra Nevada where annual snow base against the house is commonly five to ten feet for a few months at a time.
The stucco has been sandblasted and reapplied twice, I think the installer cheated the mix or something because the stucco is failing by delaminating, almost blistering, and ‘peeling’ off after only a couple years.
I would like to replace the stucco on the straight walls with some sort of siding, likely a cement product. Suggestions?
Would it be wise to apply a rock veneer to a given height?
How best to treat the round walls? Most expensive option would be to square them off. Another might be to use shingles on them, rock veneer, or even metal…
Thank you for your questions and comments! Next time I am there, I will try and grab some pictures…
arri