This is an underserved part of the market: Light, inexpensive, ventilated, rain pants. If they are not WPB, then I want full-length zippers for ventilation (that rules out LHG, AGG, Dutchware, and 3FUL).
AstaGear is the only well-known company I could find making full zip silpoly rain pants (other than custom work like Timmermade). There are also some on AliExpress.
I recently sent a pair of ZPacks Vertice pants to the seamstress to have zippers added. They are very light pants (~3 oz/90 g), but the ankles are too narrow for on/off over shoes. It’s a poor design although the fabric is excellent.
The most usable off-the-rack UL rain pants I could find (other than Asta’s pants, which are new), is OR Helium UL (~6oz). They have ankle zips and 2-layer (“2.75L”) Toray fabric (it’s a new fabric for 2026, replacing the older Pertex Shield).
(My experience has been that rain pants are better for cold weather than they are for rain (when a kilt or just hiking pants are usually more comfortable). In cold weather, wet or not, it’s great to have a layer in the pack that goes on/off quickly over whatever footwear and other pants I might be wearing. Full-zip WPB rain pants work well for that, but most are heavy.)