+1,although I wonder about a back vent and grommets. In a hard rain,the water will find its way in.

I have heard good things about these: https://www.froggtoggsraingear.com/DriDucks.shtm



but I have no experience with them (It isn't raining in SoCal these days). The price is right and they are light weight.

There really isn't any such thing as truly rainproof garments, but gore-tex and e-vent come close. If you are sedentary, PVC will keep you dry, but not if you are moving.