It becomes essential as you grow through experience that you can come up with lots of ideas around a problem.
But how will you pick ideas?
The first thing is not picking at all. As you well know, ideas need to be validated.
But they also need to connect into a design, and also from a communication perspective.
Design is essential to understand by the users, as is communication that brings them to your product.
The first step in design then is creating a caricature, or a framework identifying key areas your product will address.
This is devoid of ideas, but more an intellectual continuum. Please don't make this an achievement, it is always being evolved as you do discovery work (which happens to be done continuously as well).
The time is now right to pick ideas. And ideas need to be creatively solved. Mockups need to be made. Testing has to be started. And development needs a green light.
Without development you can never be truly sure. And with all your techniques aside, you need to launch working products. And well, they might fail.
P.S. The best part, ideas becoming solutions. Because solutions are what matter.
But how will you combine ideas?
Through LEAN thinking..