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With Open Pave, it's actually fine with 27mm as the contact point is much wider in comparison, it's the other that's what you need to worry about (like the Corsa).
@Cupcakes, you can always get the 38mm Compass tyres, as the comfort and speed are much greater and made the Palesa felt like a Marathon Plus in comparison.
However, it's one of those tyres that you do need to keep an eyes out every once in a while, and ensure the pressure isn't too high (high = risk of puncture), for me the trade off is worth it (38mm Compass, and 42mm Grand Bois).
I advise going for 28mm, as this will oddly feel like a 23mm in comparison to what you're used to, minimum 32mm.
Add a couple of mm if you have wide rims, IDK with narrow rims.
I'd be inclined to stick with 25mm regardless of which rims you have: they use the same width tread for both tyres, so there is more sidewall exposed with the 27mm.