Also note that it is very, very difficult for anyone, inexperienced or experienced, to build a monolith that can later be pulled apart. You're two suggestions are a great start. You have to really design with the major blocks of functionality in mind, and carefully manage dependencies between these blocks AND third party dependencies. So many monoliths are balls of mud, that can't be pulled apart with any reasonable effort. The code may not be spaghetti, but the dependencies and interdependencies are.