I think pronouncing it kale is a good idea and carmelo is a candy bar just fyi
To me caiden sounds like a baby name and its cute but doesnt exactly sound like a mans name. In my opinion id consider the name as a child and adult and then make a decision on it.
with that spelling people are gonna think its pronounced kale like the leafy green...just something to think about. dont want your kid hating you later in life cause no one could spell or say his name right. its gets annoying believe me lol
Caiden is a pretty common name now a days whereas caiel is rare. Or at least the spelling lol. But I like caiden better it just has a nice ring to it. Maybe your boyfriend can pick the middle name?