Design != architecture
Also, refactoring supposed to improve one and only one quality only - maintainability.
Please continue reading and understanding Martin Fowler. I would also recommend to check out Uncle Bob's thoughts on it.
Another example is switching MVC to messaging.
Design is more flexible in that sense. Please don't mix system architecture and system design.
If you have tests, you are the king. But I would expect any good mature framework to have more stability than your codebase, btw I have seen your acceptance test.
Don't put me in single camp ;) I am not a framework evangelist nor a binary simpleton.
I have now decided that you're trolling me to ensure that I don't get any work done today.
But in case you're not, or anyone wants to take you seriously:
If you so like Mr. Fowler, it will be good for anyone to understand his take on architecture:
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