I think you used the word "holistic" in a non-idiomatic way here. To me, what you wrote would mean "fond of functional programming, but don't have a broad or comprehensive perspective on it" or "fond of functional programming, but have a limited and narrow understanding of it". I doubt that's what you intended to say!

If you meant that you don't strictly insist on applying functional programming in every context or situation, perhaps "not dogmatic about it"?