Say you're starting a new project, how would you keep the complexity down? It's a hard subject and I'll admit I'm prone to follow the interesting tech.
That is, start with pure model and build outward from there. Discipline yourself to build only what you really need using TDD: only write production code for a failing test case. Only write enough production code to just barely make the test pass. This will lead to silly code. Refactor this to sensible code when all the tests are green and you sense duplication.
Avoid starting with environmental things: infrastructure, frameworks, databases, etc.
