I am the Lead Developer for a small software company. Over the past two years, my team has grown from one developer (me) to a group of about nine people. Most of us are very capable, senior engineers (20+ years of experience building software per person), so very little hand-holding is generally necessary. We use Scrum to manage our efforts, and we usually get a lot done quickly with minimal written requirements.
As the team has grown, I've reached the point where it is difficult for me to retain technical oversight over the entire project while also writing significant amounts of new code myself, so it is time for me to adjust my role. How can I make myself most useful to the team when I'm no longer spending most of my time developing?
My goal is to allow my group to grow even further (i.e. increase Scrum velocity) by adding more developers, so I don't want to simply become the "architecture police" who imposes my will on the team. In other words, I want to be the guy who helps things work better/smoother, rather than be the guy who slows things by down by adding an unnecessary layer of bureaucracy. Still, one of our main risks is that things will spin out of control if we add more people without having enough structure to keep us all on the same page.
What is the best way to achieve my goal?