Humility is an absolute essential. In every working relationship, someone has to submit to someone else. The relationship of the incarnate expression of God submitting to God as Spirit (Philippians 2) is a perfect example. The Son, though equal in essence to the Father, takes a submissive role in order to achieve redemption and reconciliation.
Agape (unconditional love) is the most important ingredient. Agape means that I take pains to care what the object of my love thinks, believes and needs. That means I will make no decision, jump to no conclusion and initiate no action without taking their thoughts, beliefs and needs into obvious and honest consideration.
All successful relationships (marriages, for example) depend on realistic unity. No marriage can successfully function, for example, when one or both spouses insist on conformity to their opinion. Healthy working relationships are characterized by healthy discussion leading to compromise and submission based on agape and humility. This will work in any relationship.
It doesn’t take a Solomon to see the application to churches. Unity is a constant theme in the letters to the churches. But it is a realistic unity among a loving and humble group of believers.