You’re on the right track with your planning. Prioritizing at least 1.5mm of buccal bone is crucial, and having over 2mm in the incisal 4mm is definitely a positive. As for the thinner palatal bone, you’re right that the thicker palatal tissue and improved blood supply can compensate to some extent.
However, when palatal bone starts getting below 1mm, that’s where I get cautious. The risk of resorption over time increases significantly, especially in areas with thinner bone. If you’re concerned, you might consider slightly under-preparing the osteotomy.
Ultimately, if you have good primary stability and the soft tissue is favorable, I’d say you’re in a good position, but monitor that area closely over time. Thin palatal bone can work, but below 1mm consistently would make me hesitate. If you have a think biotype of soft tissue then your prognosis will be much better!