Would it make sense to start namespacing options that only apply to some shader types or profiles? For example using `--fx-include-empty-buffers` or even `--fx4-include-empty-buffers`. Not necessarily this time, but maybe start thinking about it. Also for HLSL options, for example: `--hlsl-profile` and `--hlsl-semantic-compat-map` instead of what we have now.
Broadly yes, although I don't think we should just remove the existing options; at best we could deprecate them and remove them from --help.
Sure, it wouldn't be appropriate to break command lines that now work, so the current options could be added as aliases of the prefixed ones.