Interesting, in my experience Astra is a marked improvement over both Sol 5.6 and Fable 5.1. Its output feels a lot more natural, and it is just less "dumb." But individual experiences may vary.
It's a great model and you're right it does feel quite natural at times while Fable 5.1 still has a claude-ish shape to it. Unfortunately I just find that it's not reliable enough as a daily driver and ends up performing specialist tasks rather than being the primary pane of glass.