rnzoli,
Here are my 5 cents (with quite some mountain flying experience):
-first, thanks for sharing the video and asking for opinion about tricky decisions you made and also sharing options you were considering and all the planning you did (weather and other info gathered) - it shows me the maturity and professional attitude you are developing. Hovewer, considering options you were thinking about (including 180 turn in clouds close to ridge) I would only agree that you took some stuff out of your bag of luck.
I would suggest that you seriously study pecularities of mountain flying, before you fly near one in the future. Experienced glider pilots with mountain experience might be the best source, as they play with such situations often and there is other reason too: powered, loaded GA plane at high altitude might not have much climb performace left! Maybe study some glider pilots books about flying in Alps (a bible of Alpine flying is Helmut Reichmann˛s "Cross country soaring") - and yes, the author killed himself when he apparently skipped his own advice, when crossing the ridge!
Some very basics:
-do not go perpendicular across the ridge, (45 deg should do)
-allways keep horizontal visibility ahead-not only for terrain and obstacles - on your video, there was no margin in case another pilot, doing same thing, would come close. Visibility must be also behind you - in case of turnback.
-learn about demarcation line
-consider that local mountain winds and clouds can be completelly unpredictable and WX forecast does not help much. Wind is sometimes doing very surprising things- that`s why you never fly along the valley in the middle. etc..etc...
If there is a bridge across a river nearby, go there ocasionally and observe how water is doing over rocks and boulders - at high water and low water. This might give you an idea what wind is doing in the mountains-smooth upstreams, rough areas, vortices, downdrafts and what happends with wind speed increase....
Some real life:
1. gliding happily along the ridge, climbing slowly on upwind side of ridge Cu, I suddenly realised that I fell in a common beginners trap (had 100hours total): clouds became my "ground reference" so I was blown on lee side-but high enough, so I just turned straight into the wind - perpendicular to ridge. But, once into the wind, gentle climb turned into shallow descent, that became more and more worrying. Than, new Cu formed right in front of me, with ridge hidden in clouds somewhere below! (very similar scene to your video) I just kept going straight&level, sank into the cloud uncomfortably (thought it will be only for a few seconds), than a thought crossed my mind, that made me freeze: maybe I forgot to set my altimeter correctly before take-off, so I might be a bit lower than I thought! What followed, were the longest, worst, gut-wrenching seconds of my life. After I-don`t-know-how- many seconds, the sun showed again. Even now, 25 years later, this memory starts my heart pounding.
2. My colleague took off with single engine piston airplane from airfield in the mountains, heading home with two friends - a short hop of 25 minutes, but destination on the other side of the mountains. Mountaintops in the solid overcast clouds, Cb just started forming nearby and moving closely with tailwind. Pilot with instructor rating and quite some hours, but most in the flat landscape.
GPS track showed that plane entered a valley in general direction of intended course to cross mountains, but terrain "climbed" faster than the airplane on full power, until it became too late (narrow) to turn back safely. Plane hit the ground in near vertical position, all three aboard died.
Stay safe and learn from experience and mistakes of others- you will not live long enough to learn from your own!
Regards,
hoistop