Actually we can plan for a 5.12.1 shortly after. It is more important to have a stable release out before we start breaking things, so maybe we kick some of the issues to the patch.
#9018: Model turns black under transformation containing reflection actually needs more discussion. When working with transforms, the black model effect is a good suggestion that you may have accidentally done an orientation-reversing transform. Auto-fixing normals could hide one of the best ways of catching certain kinds of mistakes like this. Instead we should consider adding a flip normals or auto-normals feature that can be explicitly invoked.