In an affordable rainproof (not merely rain-resistant, but rainproof) cycling jacket, I'm very satisfied with the Shimano Storm Jacket I got in 2015. Kept me warm and dry through some chilly downpours. They're discontinued but still occasionally available as new/old stock for $50 or less from a few discounters. Shimano made a few variations of the same basic jacket, all for serious rain rides. Laminated shell, mesh liner, excellent attention to detail overall, well worthwhile if you can find one.

Downsides: It doesn't breathe and the ventilation could be better for warmer weather (above 60F). It just has a cape vent and needs to be unzipped for flow-through ventilation. I'm thinking of having a tailor add some metal mesh grommets in the arm pits. That would handle most of the heat/sweat buildup. And it's relatively bulky - it might fit a ziplock gallon bag with some effort, especially if you skip the detachable hood.

The Pearl Izumi Select Barrier windbreaker has been rain resistant (I haven't had a chance yet to try it in a real downpour) through light and misting rain, very wind resistant and remarkably comfortable from the 20s with appropriate layering to the 70s with a single thin jersey underneath. The least expensive PI jacket I got has no cape vent, armpit vents or detachable sleeves (the higher priced PI jackets do). But ventilation has been adequate through the rear waist pocket by unsticking the Velcro fastener and unzipping the front at the collar. And the fabric may be the thinnest possible fabric that's still practical. It'll roll up into its own rear pocket, and squish into a quart size ziplock baggy with plenty of room to spare, or stuff into a jersey pocket or my handlebar pouch or saddle bag. No hood, just elastic wristbands.

High end Gore-Tex is out for me. I already have a rain-resistant winter parka with Gore-Tex shell and Thinsulate insulation. Very expensive but it's served me well for almost 30 years, including some bike rides this winter in temps down into the 20s.