This is a very short answer, and is given without all the usual qualifications. For those, you will have to review the many hood topics on this forum, or study the literature referenced in the topics I have collected under My Clippings.

Hood aperture should overlap the cooktop by enough to capture rising and expanding effluent. Three inches on each side and front is typically used for normal use against a wall where air flow is sufficient. Drafts can interfere with this.

Actual minimum flow rate at full blower power should be (in my view) at least 90 cfm per square foot of hood aperture. Blower rated flow should be around 1.5x this value x the aperture area. Duct size should be sufficient for the actual flow rate to cause between 1000 ft/min and 1500 ft/min of velocity. Aim toward the higher value if the ducting is cold in the winter.

Baffles will provide more flow with less cleaning than mesh filters.

Establish hood height to avoid head bumps and sight-line blockage. However, the higher one goes the greater the hood aperture should be; the 3 inches above is for the range of 30 inches to, maybe, 36 inches above the cooktop.

Aesthetics, Economy, Performance; expect to achieve only two out of three.

kas

There's a guideline that you need 100 CFM of ventilation for every 10,000 BTU of range heat output.

And what kaseki said - 3" overhang on either side. I picked a 42" hood over a 36" range for that reason. 42" Futuro Acqualina over the Verona VEFSGG365 gas range with 5 burners.

I don't think the ovens really factor into the hood equation, at least I haven't seen it brought up in discussions.

There have been a very few oven ventilation conversations on this forum, but not conclusive ones. In general, the massive effluent output of a just-opened oven door could overwhelm almost any vent system established for normal kitchen use.

Further, range oven doors open beyond most hood overlap dimensions, and wall ovens often have no vents near them at all. The solution of having ovens with internal vents to external fans is not one that is presently in vogue.

There is a point of maximum practical residential configuration, and that point will still have limitations. To go beyond that is to go commercial with both ventilation and clean-up techniques. (Imagine an all-tile kitchen with steam cleaning to a grease-trapped drain in the floor.)

kas