I assume that the cabinetry will be painted a color. I would paint the transition the same color as the cabinets - otherwise, I think your crown will look like it continues down too far = it will make your cabinetry look short + make your crown look too thick.

For some reason my initial comments didn't post with the pics. I just edited it

I think that painting the entire wall of cabinets with the dark green, including the trim doesn't mean that you need to paint the other trim the same color. I think it will look more cohesive to paint the other walls and trim a different color, if I'm understanding your dilemma correctly.

I also like dark trim on light walls, but you already stated you don't care for that. Sorry no photos to show--I've looked online.

I think you have painted yourself into a corner!

With a built-in that touches the crown, it never looks good in different colors.

This would have looked awful with white crown.

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This is the reason why built-ins are sometimes not carried to the ceiling ...

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Crown same color as built-in, but rest of trim still white.

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Crown is different color than built-in/cabinets. Don't like this as much.

I would rather continue the green above the cabinet and have it transition to white over the walls.

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Blue crown over cabinet meets white crown over wall. I prefer this look. A white stripe over the top of the built-in would look terrible!

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I would do it like this - matching the crown to the built in.

I would paint the transition the same colour as the cabinet.