I have been using the Torrent Shell rain gear from Patagonia as my go too for a few years but the packability and weight were an issue and always wanted a better solution. This years trip to the Andes in Peru I took a TerraHiker poncho:
https://www.amazon.com/gp/history?ref_=nav_timeline_view_history
Light and packs down to nothing. performed very well in the high winds and heavy rain at above 14,500' for 2 weeks. This is now my go to and I can live with the short comings of a poncho versus full coverage. It breathes well.
It is loud, like the Torrent, but have found nothing worthwhile in the rain gear category that was quiet and did the job. It does fully cover the backpack so no issues there either.
If I were in an area where rain was a normal everyday occurrence, and the temperatures were low like in the low 40's and lower, I would stay with a full coverage rain suit.
I ended up buying 8 more of these for friends in Peru who were in impressed with this poncho.
Cost of these are around $20 so well worth a try.