Just off the cuff I'm not sure a MCP manager has got quite the scope for a SAAS offering, at least not if you're just managing config. There might be a play at the enterprise level if you can integrate deeply with domain policy.
Mostly I find working with MCPs pretty easy, but there is some minor benefit to hosting mcp servers that are more involved to set up. The thing that I would pay a small amount for (which is why I'm building it myself) is a MCP oracle that configures the MCP server set for an agent based on the task it's working on.