Having jaw surgery is ultimately something you decide. Something that looks minor can be a big issue to someone else, jada jada.
Base on what I read you have no medical issues and it's a pure aesthetic concern. Your bite was corrected and you don't mention anything about airways. One important thing to understand about jaw surgery is that it alters your bite, and there's always a risk they don't get it right. For most people having jaw surgery that's a minor risk, because they go in with a malocclusion. Trying to fix something that is broken is necessary, while fixing something that is not, takes some balls.
Your aesthetic concern doesn't seem very established. You're not sure if lower jaw surgery was the right decission so you go consulting and get some proposals and we later get some concerns about tooth show. Tooth show is a concern that can be adressed with jaw surgery if it's a real concern. But you understand it makes little sense when you present your situation with profile photos and ask if you should have surgery for your consern about tooth show. You will get comments on what can be seen on the pictures you show.
Your surgical plan is not clear to understand at least for me. "advancing upper jaw vertically by about 2mm and downgrafting it by about 3mm". Vertical adjustments are normally not denoted as advancements, I can't read what these mm mean and how it's actually displaced. You talk about rotation and flaring teeth inwards, so probably clockwise rotation. If you already have a good bite, and you're doing only upper jaw surgery, it needs to be done in a way to maintain the bite.
You've been told upper jaw surgery is a minor surgery compared to lower jaw surgery. There's no way to meassure such thing, it's different fractures. I can tell you, lower jaw surgery is sometimes done under local anaesthesia, which upper jaw surgery is not. Go to youtube and watch some videos of "lefort I surgery" and "bsso surgery" and come back and tell us what you think is minor and major.
