The airways in the flight plan are built using the default G1000 code. ie. Always been there. V speeds require far more calculation on Saso's part, due to having to take into account several factors and implementing a boat load of more math. Making it compatible with Vulkan/Metal is taking priority at this time.
As for your other comments.
Taking the yaw away? We had people screaming for it to be reduced, as it was deemed too unrealistic and exaggerated. We consulted a TBM pilot and engineer and we received feedback, which was implemented. Some people don't like it, and some people do. What can I say...we can't make everyone happy.
Absolutely no texture resolution was sacrificed in exchange for improving framerates. Framerate improvement came from further code optimisation. I don't think I've seen anyone ask for WORSE framerates and higher texture resolution.
The whole point of a TBM 900 is to actually make it less difficult to fly than, say, a TBM 850, by way of more automation and less clutter on the panel. It's supposed to be easier.