A healthy community has a culture of open-mindedness, by which I mean individuals are in the habit of looking at a problem through multiple lenses. The way you do this is by inviting feedback and moderating constructive discussions.
The ideal process goes something like this:
This process isn't necessarily linear; for complex problems, it is often helpful to circle back several times, reevaluating assumptions as needed, in order to avoid arriving at a local (vs. global) optimum.
If you have a very small community and/or don't have the luxury of being able to participate in realtime discussions, you may have to trick your subconscious into keeping an open mind, and not prematurely narrowing the field of possible solutions. One way to do this is to write down a defense for why you prefer one option over another. This forces you to get outside your own head and broaden your perspective, even if you don't immediately have the opportunity to share your defense with anyone else.
Let's get creative.