Here's the thing about Little Greene's French Grey: the name's a bit of a red herring. It reads as a gentle, dusty green-grey, and the trick to making it sing is to lean into the green rather than fight it.
Start overhead. Keep your ceilings and any whites warm and chalky — never a crisp blue-white, which will make French Grey look cold and a little sad. Something soft like Dulux Almost Pistachio (LRV 80.3) works a treat as a barely-there off-white that nods to the green undertone without competing. That's your light, airy partner.
For contrast and depth, go richer in the adjacent joinery or a feature wall. A deeper sage or olive in the woodwork grounds the whole scheme and stops it floating. If you want proper drama, Paint & Paper Library Blue Blood (LRV 16.4) is a gorgeous moody anchor — used on a lower panel or a single wall it gives French Grey something serious to push against. Or for warmth, Mylands Cigar BH.20 (LRV 11.8) brings an earthy, tobacco depth that flatters the green beautifully in skirtings or a fireplace surround.
The but what about metal? question always comes up. Warm brass, every time — antique or unlacquered. Chrome and cool nickel will fight the green and make the scheme feel disjointed. Brass picks up the warmth and ties it all together.
French Grey also looks cracking colour-drenched — walls, woodwork, ceiling all in the same shade onto panelling. It's quiet enough to take that treatment without overwhelming a room, and it gives you a sophisticated, enveloping result that flat-white-ceiling schemes can't touch.
Practical tip: it shifts noticeably with light, leaning greener in bright daylight and softer, almost grey, in the evening. Get a sample on the wall and live with it for a couple of days before you commit — especially in a north-facing room, where you'll want to be sure that green undertone is doing what you want.