I think both seem cute for middle names.
I quite like Evelyn Honey. It may seem a bit cutesy to some, but I've heard of enough Honeys now to see it as a proper name (plus it's #200 in E&W now). I think Amelia Clara and Evelyn Honey would go very well together :)
Darling does seem a bit weird as a proper name. Although it's a lovely term of endearment, it mainly reminds me of the Blackadder sketches with Fry & McInnerny :D
My brother wanted to have two daughters and name them Evanelle Honey and Lily Sugar. He planned to name their brothers Jack Hickory and James Rebel. He actually did name his one son James Rebel, we call him Ol' Reb. I do not know what we would have nicknamed Honey and Sugar, but Jack Hickory just makes me think of barbecue sauce. Anyhow, point is, I would personally save Honey as a term of endearment and not as a legal middle name.
I think anything goes with middle namesake paired with a lovely first they would be fine, especially as most people at her wedding will assume Darling was your maiden name when the vows are made (for instance).
That said, these aren't my taste and I think there's a danger that what sounds cute on a tiny tot sounds stripperish or simply childish on an adult - one day she may be a 45 year old civil engineer in charge of a major project - she's not going to be wanting to be called Darling. In giving our daughters names suitable for home, stage or screen but not for a dentist do we subconsciously send them a message that we don't see them as a future prime minister or working in a 'serious' field?
I grew up knowing an older lady named Honey, and always thought it was such a sweet (pun not intended!) name. As a middle it is perfectly fine.
Darling, on the other hand, is a bit too much for me. I actually think of Lady and the Tramp where the dogs perceive their owners' names to be "Jim Dear" and "Darling."