If your hood is mostly for show, and you rarely if ever cook smoky or greasy things like steak or stir fry, you can get away with that designer hood you've pictured. Its objective is about appearance, not about function.
Since your designer suggested that hood, either s/he doesn't care about function, or thinks you don't.
If you care about exhausting smoke and grease of your cooking, you need:
- a hood in a canopy shape to provide capture area
- the exhaust duct that goes from the hood to outside should have a diameter of 8" or 10", not smaller.
- hood filters that are baffle filters not mesh (your OP's third photo shows a baffle filter). That's because mesh quickly becomes clogged with grease if not cleaned often, which blocks the exhaust. Baffle filters need to be cleaned too of course, but the hood's effectiveness won't be impeded if you don't.
- ideally the hood should be 6" wider than the cooktop for best capture area. Many people can't afford to lose the 6" of upper cabinet space though. But then at least make sure the depth of the hood is sufficient front to back. Many hoods are only 20" deep, leaving the front burners uncovered. Try to get a hood that is 23-24" deep.
- the distance from the cooktop to the bottom of the hood should be 30"-36", not more or less than that range.
- try to shoot for 600 cfms. It's sufficient for most cooking tasks (assuming your duct diameter is sufficient), and higher cfms than that would require makeup air which is costly.
Q