It looks like the optimal pattern is to have Astra as the orchestrator and Sol as the implementer. Same as with Fable and Opus.

I've found Sol to be an excellent orchestrator, with Astra the planner and Sol again the implementer.

I've found Astra to be horrible at making orchestration decisions. I will be trying to use Sol for both. Fable is very good at it though. Worst part of my week is when I hit my Fable usage limit and have to switch to Astra.