If you really want to go with ventile and/or gabardine in *very* wet environments, there is an option worth considering: carry a silnylon poncho with you.
A stuffed silnylon poncho isn't much bigger or heavier than a pack of cigarettes (OK a pack and a half of cigarettes) and it's completely waterproof.
You can carry one -- completely unnoticed until you need it -- in a pocket, or possibles back or rucksack.
Combined with a ventile or gabardine jacket, you have a nice system with a silnylon poncho. To wit:
1) In a light rain or snow, you just wear your ventile or gabardine jacket and have the silnylon in your pocket or possibles bag or backpack.
2) if it starts to come down heavily, you put on your poncho and it takes the lion's share of the rain-shedding duty -- you still have all the advantages of ventile or gabardine beneath it. It's a breathable and flexible approach. And since the gabardine/ventile jacket can shed a lot of moisture, you don't worry too much about gaps in the poncho.
3) a bonus -- if you use a silnylon poncho, it can serve as a minimal tarp if you decide to wait out the storm. If you buy -- or make -- a poncho, just make sure to have one with tie-out points. In other words, with this system you *always* have a core shelter with you.
3.5) another bonus -- a silnylon poncho will also cover your pack, sparing it from the moisture.
You can buy silnylon ponchos or you can make them yourself if you've got access to fabric and basic skills with a sewing machine.
In the US you can often find enough silnylon fabric for a poncho or tarp at (boo, hiss) Walmart for a couple of dollars in their discount fabrics bin. It can be a trick to sew because it's so slippery, though.
Personally, I think goretex and event etc. are just fine and I look at the prices of ventile and shudder -- so I have never tried Ventile myself. Gabardine, however, I do use and like a lot and it's not as dear.
But I've never burned a hole in goretex one with a popping ember -- after all, embers aren't ballistic. Maybe I've been lucky. And because I'm on the west coast of America and usually do low impact camping, I don't build as many fires outside of the hobo stove as it sounds like you do in the UK.
But here on the West Coast, I've got as much experience in wet woods as you do in the UK and I can promise you the silnylon combo approach I recommend works well and has genuine benefits.
