The Ghillie Shirt

[Tobus]

Would I be right in thinking that black ghillie brogues with the ghillie shirt would be the kilt equivalent of 'smart-casual'?

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Personally, I believe the ghillie is a smart shirt and looks great when done correctly. I know the shirt is extremely informal and the black brogues are formal, so I imagine this would give off my desired look of smart-casual and romantic.

To be honest, when I think of "smart-casual", the ghillie shirt doesn't even enter into the equation. Everyone has their own idea of what constitutes a "smart" (or its equivalent "sharp" in the USA) look. For myself, I don't see how a shirt could be smart at all when it can't be buttoned up and worn with a tie. As you said, that shirt is extremely informal. It's meant to look outdoorsy, quaint, and folksy. It's designed to be worn with the laces loose, and open at the neck. Lacing it up and tying it closed still wouldn't come close to the smart look of a traditional collared button-up shirt with overlapping seams at the buttons.

Mixing the folksy ghillie shirt with other items that may have a dressy appearance doesn't really up-scale the whole outfit. It just becomes an odd pairing of different levels of dress. Neither fish nor fowl, or perhaps fish and fowl fighting with each other.