I'll be honest with you. I had kinda stagnated over the last couple years when it came to improving my skills as a developer. When I first started developing professionally I went from not knowing much PHP to being well regarded as a developer in a few years.
Part of my improvement came from building one content management system after another for the first 3.5 years. Lots of iteration and certainly a few big mistakes.
But then I hit my stride. I was writing good code and there was no real external pressure to improve. Things are different now.
I don't have any external pressure in the form of people telling me I have to get better. It's more like the external pressure of supporting code I wrote 2 years ago and finding all the areas that really need to be improved.
My app was built on Kohana 3.1 which is a nice framework but was not really built on a test-driven development methodology. There are a lot of static methods. Take a look at this database example and see what's typical.
I was thinking that the solution would be to build an API on Symfony and then rewrite the site to just be a front-end calling API methods. This may still be the final solution, but I think first I need to reorganize and clean up the existing site. There are certainly ways (as illustrated in the Robert Martin video) to write well-tested code that is outside of your framework and you use the framework as a delivery mechanism. Once I do this, I could theoretically take the code I'd written and move it from Kohana into Symfony if that makes sense and I won't have to reinvent the wheel.
We do a lot of complex SQL queries so it's about time to get off the ORM so I can fine tune and optimize my queries and database tables.
I'm learning to stop myself and ask "Is what I'm proposing actually the best idea?" and "What other things could I do to solve this problem?". If I force myself to come up with a few possible solutions I'll probably find that my first solution was not optimal.