I think harness/model pairs matter more than your analysis lets on.
I've had great luck with the ds flash v4, paired with prime-agent for the harness--I like the results a lot. And you get to see thinking tokens.
I haven't liked the model as much in opencode.
Sol & luna have been great everywhere. sol plans, luna builds.
Prime Agent looks really interesting. Both the "recursive language model" bit and routing everything through IPython.
https://github.com/PrimeIntellect-ai/prime-agent