Looking forward to answering your questions later today.

1) Short answer is "yes." A small distance outside of the clear aperture may also be effective. In the case of my Wolf Pro Island hood, I count the inch at each end and back, but not the higher curved part that adds to the specified dimensions. I count an inch of the light bar zone also, which is significantly larger. This is really in the noise, though, given the ability to estimate baffle pressure loss, among other things.

2) Not me.

3) It doesn't help if containment is perfect (which is our goal) if some of the effluent plume is not captured. To the extent feasible, determine the contour of the largest pans you might use on all your burners. Determine your hood height above the pan bases and multiply by the tangent of 10 degrees. (This is the minimum; somewhat larger angles can be argued for in various circumstances.) Extend the outside edge of the pan contour all around by this height x tangent value. Your hood capture area should encompass this larger area. In your case, the back is a wall and the hood need not go any farther.

Larger containment volumes (significantly larger than residential hoods provide) allow averaging of the highest velocity plumes over the baffle space allowing commercial hoods to get away with somewhat lower CFM for a given capture aperture area.

4) @opaone's noise charts. I don't have an iphone to use to contribute values with.

If you use an external or in-line but distant blower, and install a silencer such as Fantech makes in the path from hood to blower, the blower blade tip noise and upper duct turbulence noise will be significantly reduced. My roof-mounted Wolf/Broan 1500 CFM rated (at zero static pressure) blower pulling an actual ~ 100 ft/min across my hood capture aperture is fairly well attenuated such that the dominant kitchen noise in the voice band is baffle hiss. This might vary with baffle design.

5) I can't answer specifically, but with my hood blower on full power one can converse at normal talking level with someone on the other side of the hood or a few feet away. From the cook's point of view, Intelligibility of a TV in the open room on the other side of the peninsula requires a modest volume level increase over listening with no blower flow.

In my opinion, find a hood that best solves your optimization of the trade space of capture, aesthetics, cost and use an appropriate remote blower with a silencer, and you will find the noise is attenuated enough. If you follow the general "prescription" of @opaone's commercial setup, you may be able to run lower flow rates from a large enough blower that the noise is negligible for most cooking tasks. Opaone has discoursed on this in a number of threads that should be reviewed.

6) The more the hood design approaches a commercial configuration, the more volume below the baffles you will have. See this thread for a relatively practical quasi-commercial solution.

https://www.houzz.com/discussions/6204496/range-hood-questions#n=8

Thanks a lot for the detailed reply, @kaseki, much appreciated! Will definitely look a further into doing a commercial setup (I had assumed commercial setups would cost a lot more than a custom hood, but from that thread it seems like the cost was comparable).

Had one quick follow-up if you have time: I saw in a separate thread that you had mentioned that you believe the performance trade offs of a chimney-style hood are not worth it (I imagine something like https://www.pinterest.com/pin/65020788347340134/). Why is there a performance trade off for a chimney-style hood like that as long as the chimney itself is large enough to be comparable to a 10" diameter duct?

Thanks!

Trades are only relevant in context of all the aspects being traded. I have no objection to hoods of that general configuration, so long as they are sufficiently large in capture area, have baffle filters unless there is some overriding reason for mesh filters, and have sufficient flow rate for containment. My Wolf Pro Island hood is effectively of that type, only much larger. Generally, useful residential hoods are commercial hood configurations that have been figuratively mashed into smaller volumes and prettied up to the point where the relationship is hard to discern by the casual observer.

Please link the thread so I can divine why I wrote whatever I wrote.