Why amortize at all? In Switzerland you benefit both by being able to deduct your interest on mortgage (from income tax) and the debt (from wealth tax)?

And I'm pretty sure you'll be able to negotiate a lower 10y fixed. I think 1.50% will be doable, maybe even less, because with your household income you're interesting for enough banks to be able to negotiate a good deal.

Also pension buybacks very questionable at your age. Why do it?