I have been know to double up rain gear along the rainy coast.

Once i used old goretex rain pants as my regular pants with light rubber bibs over.

Condensation was trapped in between the layers and I was quite comfortable. We were not hiking where there was a lot of elevation gain tho. so we weren't overheating but we were in inch+ per hour rains.

I have also been known to bring a poncho and jacket and pants. Then I had different options for wind, brush, ventilation and I used the poncho as a vestibule for my tent to cook under at times.

Frog Toggs are cheap and light and breathable. They make ponchos and whole suits. Maybe jacket, pants and poncho. Still might be lighter than a heavy duty rain suit.