It seems like there are 3 basic questions here:
- Can it be done?
- If it can be done, should you use it?
- Should the developers spend development time on it?
For 1), I think pretty clearly all sorts of options, including various performance styles, could be done.
The second question is sort of the tricky one. I’m all for using AI and proofreading algorithms to help me with busy work and to catch mistakes, but it seems to me that 90% (at least) of writing really is the process of writing. If haven’t experimented with various themes, harmony, orchestration, etc., to find out what works and what doesn’t, and just relied on software to do it, then I wouldn’t really understand what’s on the page, and wouldn’t understand how to go about revising it or getting the best performance out of it. A forklift is way better at lifting weights than I am, but I don’t take a forklift with me to the gym. The goal there isn’t to physically move the weight, the goal is improvement by the process. The compositional process itself is important too and you lose a lot by simply bypassing it or relying on software.
For 3), that probably depends on whether the developers think it’s worth the time cost and whether it would be marketable. New versions need marketable features to attract people to upgrade. None of the things the OP posted would really be that interesting to me personally (I like minor 9ths and know how to use or avoid muddiness), but perhaps Steinberg’s market research says that it would be a popular feature. Or not. It definitely seems to be straying a bit from a dedicated emphasis on notation, although we already have features like Generate Chord Symbols and Generate Notes from Chord Symbols. We’ll have to wait and see what D6 brings!