Your belief of a design is confirmed in Ephesians 4:
11 And He Himself gave some to be apostles, some prophets, some evangelists, and some pastors and teachers,
12 for the equipping of the saints for the work of ministry, for the edifying of the body of Christ,
13 till we all come to the unity of the faith and of the knowledge of the Son of God, to a perfect man, to the measure of the stature of the fullness of Christ;
14 that we should no longer be children, tossed to and fro and carried about with every wind of doctrine, by the trickery of men, in the cunning craftiness of deceitful plotting,
15 but, speaking the truth in love, may grow up in all things into Him who is the head----Christ----
16 from whom the whole body, joined and knit together by what every joint supplies, according to the effective working by which every part does its share, causes growth of the body for the edifying of itself in love.
My vocation is technical (electrical engineering) and my views cause me to determine how a mechanism is designed to operate. The One Who designed it nailed down parts and pieces that show a massive forethought that some of us are in the catch-up mode trying to determine. There are others who fit into God's plan to address other aspects that we aren't attuned to. The goal of the different roles we serve in is the same, however - avoidance of garbage theology that is "every wind of doctrine, by the trickery of men, in the cunning craftiness of deceitful plotting".
I think there are many more absolutes than is generally recognized. With this I don't discount the liberty Jesus Christ purchased for us to enjoy, and perhaps the area you consider gray is in that realm. That was part of the design, as well.
Matthew 17:24-26
24 ¶ When they had come to Capernaum, those who received the temple tax came to Peter and said, "Does your Teacher not pay the temple tax?"
25 He said, "Yes." And when he had come into the house, Jesus anticipated him, saying, "What do you think, Simon? From whom do the kings of the earth take customs or taxes, from their sons or from strangers?"
26 Peter said to Him, "From strangers." Jesus said to him, "Then the sons are free.
God's redemption as His adopted children has given us the same freedom over the law that the law's Creator enjoys. That freedom is the essence of liberty.