I'm a matcher and have matched some pretty intricate backings.
Why? .... because I know I would never be happy if I did not.
Plus, I like the look of the whole cloth print, when a quilt is flipped over.
Gives it a dual-purpose look and doubles the usage.
Your butterflies are pretty enough, that they deserve to be matched.
If you do not have enough, you could do some inserts and save matching the butterflies.