I would also like to know — I think people are using Cursor/Windsurf/Roo(Cline) for IDEs that let you pick the model, but I don't know of a CLI agentic editor that lets you use arbitrary models.
Hey, I'm the creator of Plandex (https://github.com/plandex-ai/plandex), which takes a more agentic approach than aider, and combines models from Anthropic, OpenAI, and Google. You might find it interesting.