Some good thoughts. We can get a good picture of God's priority on unity by studying Jesus' prayers recorded in John 17.
First Jesus prays for Himself that God's plan would be fulfilled as He was to be glorified. Then He prays for His disciples, that God would protect them as they would lay down their lives to live and preach the gospel. When He prays for us it is that we would be united!
John 18:21 "...that all of them may be one, Father, Just as you are in me and I am in you. May they also be in us so that the world may believe that you have sent me."
The stakes are pretty high when you think about it. Unity in not just so we can be friends, but it is so that the world will believe this good news that we preach.
When you look back at church history there have been times when a division had to take place. Many have given their lives to defend the faith from those who would distort and destroy it. The church is always at risk because of false doctrine and true believers must stand firm. Other than that we must learn to live and work together as the body of Christ.
I believe we should embrace the motto made famous in the restoration movement "In Essentials, Unity; in Non-essentials, Liberty; in All Things, Charity."