Slate doesn't last as well as tile under the combined influence of sun and rain. Since architects began being sued for leaks, metal roofs have increased in frequency. Stainless steel and copper are the leaders. After the roof, the windows are the most vulnerable. The catalog of problems presented by windows includes cavities and seals, condensation and moving parts.
Walls have a lot of options, none of which is ideal and most of which have fatal flaws.
Aluminum and vinyl siding conceal problems until they fail disastrously. Curtain wall masonry is attached by metal parts which fail in 100 years or less and are virtually impossible to replace. Clapboard looks bad before it is bad but at least it can be painted regularly and replaced piecemeal. New materials are unproven by definition and, like most experiments, they tend to fail. If used widely, they fail big.