If a rain jacket it all you think you need, either you are not really going to be working in rain, or you are not experienced in what working in the rain really means. Rain pants, or much better, bibs are an absolute must as well.
In all my many years in the field, much of it in rainy weather per normal here in the PNWet, I have never found a single bit of "breathable" raingear that was worth a bucket of warm piss. You can spend several hundreds of dollars, and it may well work barely "sort of" if you're not doing much physically, for a year or 2 at most before the magical pores get fouled with body oils and dirt and it leaks under any really wet conditions...but even brand new, if you are working hard, it still will sweat from condensed body heat on the inside enough to make it very little different from having no rain gear on at all.
Less expensive "breathable" options are only less money wasted, as I have found from many a dollar expended in wishful trials.
So here is my hard learned advice. Buy the best full on waterproof stuff you can afford...offshore fishing gear like Helly Hansen is worth a look. I did better most times with lesser priced heavy waterproof lined nylon bib and coat sets, just because the likelihood of getting damage from abrasion and rips was high in my work in the brush, so a couple or maybe three years was full life expectancy.
Wear synthetic undergarments...nylon, polyester, fleece. Avoid cotton undergarments like the plague. If it is really wet out and you have hard physical demands, take a change of ALL undergarments (not just underwear, I mean everything, all layers) to work and swap out to the dry clothes during lunch break.
Give up the dream of staying really dry. You will not. You can only mitigate the wetness to some small degree.