In my opinion, the raincoat is much useful than a poncho that will be uncomfortable and the wind will blow it anytime. Combine raincoat with a waterproof cover for your rucksack
and you will do much better.
I don't know how works for others, but for me the lighter backpack was better. You don't really need too many things on Camino. See my Camino Gear-FULL LIST
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