Odor elimination requires complete capture and containment of cooking plumes. These plumes expand as they rise, deviate due to drafts from hot air furnaces and/or air conditioning, and spread due to turbulence from moving people in the area. Normal hoods are placed in the zone between 30 and 36 inches above the cooktop. That is, to 6 feet above the floor. Commercial hoods, usually larger in capture entry area, are typically set at 7 feet unless one counts ceiling systems. (See Heydal's ceiling for example: https://cms.esi.info/Media/documents/Brita_heydal_ML.pdf) One can always use a commercial system that grows appropriately at any height. However, these are not only large in plan view, but tall in elevation view. On top of this, you need to consider, or specify, what your ceiling and joist characteristics are and if there is an attic above or a living space. Wolf makes a ceiling mounted hood, and the descriptive information appears on pages 139 through 142 of the Wolf Design Guide, available at Wolf's web site. The available units are only 21 inches wide in the short dimension. I would consider this to be ineffective in capture of any significant plume such as hot oil cooking (searing and wok cooking). I'd want a 5 ft x 4 ft aperture at 8 feet up, and thus embedding a custom commercial hood into the ceiling would be necessary if buying three of the wolf 4-foot units wasn't practical. Also, please note, I've never seen one of these, and have no idea whether I would consider the design details acceptable. I would think that such a collection area would need 1500 CFM rated (1000 actual) if we assume significant degradation of plume upward velocity; even more would be required otherwise. Make-up air is required for this level of flow rate. Most locations will need heated MUA. With filtering, the MUA might be OK passive (without blower), but if there are any combustion appliances that are using air from a space connected to the kitchen then a blower-driven MUA will be needed. (MUA threads here may be viewed for background.) If you want to consider a commercial based hood as a likely better choice if there is an attic above the ceiling to fit it into, @opaone may come by and provide some additional information, including what I don't know for gas flame combustion products expanding potentially wider than the cooking plume and air quality effects resulting therefrom.

Has anyone found benefit in these? They are a considerable distance from anything placed on top of the range. Stuff on a back shelf is closer and of more benefit but that can be a bit of a pain reaching across whatever is on the range. I've never known anyone who had them that wanted them again. They also reduce the capture area and containment area of the hood and so reduce its effectiveness. These are about $50 and get a lot more heat a lot closer to the food. Can be a bit of a pain to store though: 1126711.jpg

any style really, like fabric -- need to be adaptable for slightly sloped ceiling

A wall location is much easier to accommodate cooktop ventilation than an island or peninsula configuration, but the extent of this truth somewhat depends on what is above the ceiling, and what the ceiling height is, and whether this is new construction or a renovation of existing architecture. The higher the hood entry aperture, the larger it has to be. Conceivably, with an 8-foot ceiling, a one-foot high assembly based at 7-feet height might be feasible. It would have to be commercial sized in its entry aperture (say 6-inches of cooktop overlap in all directions -- 3 x 4 over a 2 x 3 cooktop). In such a case, it could still have proper (albeit low angle) baffles and a containment volume above to a duct to outside. Cleaning would be more difficult with a hood base 48-inches above the cooktop than with a hood base 36 inches above the cooktop. I am not aware of any such hoods provided by the higher-end residential hood manufacturers, but am confident that if suitably encouraged, a tailor-made (bespoke) hood by ModernAire, for example, could be fabricated. You would still need a path to the outside, either through an attic, or chase in a room above, or horizontally if the joist heights provide sufficient sectional area. Twelve-inch duct might be needed. With sufficient floor stiffening, a deeper hood could be inserted into the joist space (in new construction) by framing out the area and providing a horizontal feed to an appropriate joist path. With additional height, baffles higher in the assembly could be used and potentially modestly less CFM would be needed. However, vertical ducting is greatly preferred, and avoids the potential for grease accumulation. Please be aware that the higher the hood entry aperture, the more susceptible the rising and expanding plumes are to transverse drafts, and even turbulence from people moving about. If there is a static direction of flow from air conditioning, for example, some growth over my 6-inch comment may be needed.