Not an expert at all, but I think it would be odd to continue the wood all the way to the wall as it would be above drywall there but above cabinets everywhere else.

Might the dark color cabinet installation look rather heavy with all that wood covering the 9" soffit to the ceiling? Here's a photo of what you're planning with white cabinets.

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Would it be undesirable to just leave the soffit exposed?

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A

@HALLETT & Co. Did you mean to say something else?

Nope. End at A. Running it to the bay window would be ridiculous

@HALLETT & Co. Thanks for the clarification and your feedback is very appreciated.

@PPF. Thank you so much for your helpful suggestions. If the riser is to be flushed to the wall, part of the bulkhead needs to removed. Is that correct? Also, there will be a gap at the top of the crown (circled in red) in your picture below.

He already showed you in his illustration what to do, the crown moulding is mitered at the end and returns to the drywall. You really should remove the last 6” of the soffit and pull the base cabinets back the same amount. This allows the crown to die into wall and the countertop isn’t sticking past the wall.

There are a bunch of variables at play here. Consider your backsplash and countertop -- where and how will they end? Try to think through everything. So many do not and come here with problems that are not easily solved after the work is done.

part of the bulkhead needs to removed

Correct

Also, there will be a gap at the top of the crown

Not sure what potential gap you are wondering about, but the crown gets a return back to the wall.

@PPF. Will it look good if the overhang B is 3/4" and overhang A in the front is 1-1/4" (green and blue arrows inserted in your picture below)?

If the soffit will overhang the cabinet, I'd strive for an equal amount side and front (from face of door, not cabinet).

I would also add a trim piece as shown at the bottom of the soffit. This will help disguise imperfect alignments.

As for your question, no one will notice a 1/2" difference, but try for consistency throughout the kitchen.

@PPF. The bulkhead (soffit) that will be covered with the crown and riser, will protrude out 1-1/4" over the cabinet doors. Adding the trim piece (3/8") on the bottom of the riser (see picture below), will make the bulkhead protrude more. The total overhang will then be 1-5/8" (1 ¼”+3/8”). Would that still be ok?

Would that still be ok?

Yes

@PPF. Thank you so much. Your help is very much appreciated.

It's corner bead. Google for lots of info.

@PPF. Thank you very much for the information.

The picture below shows the drywall and corner bead were removed from the edge of the bulkhead. To install a corner bead in the corner circled in red is not possible as that corner is 1/2" and has no stud. A riser (wood panel) and crown molding will cover the entire bulkhead, could you please advise what needs to be done where they will meet the drywall (circled in red)? The riser will flush with the wall.

Thank you.

You could use an L bead, or modify a standard corner bead, or just use drywall joint compound.