I recently had a foot of sticky heavy snow on a silnylon BD Mega Light. No bivy sacks. It was sticking to the exterior even with some wind, which caused extra Extra condensation and maintenance. So steeper than that would be good. I've heard the Golite Hex is better.
On another trip, the wind also badly damaged the fabric at the webbing X at the top, or was it us pitching it too low?
We found it was nice to have something blocking the open bottom, either from blowing snow or dust (that was bad), often using our packs. If there is enuf snow, that was not a problem. Also, we usually (summer and shoulder season) use heavy rocks rather than stakes, so abrasion resistance is key on the tie outs, but also the fabric around them. I file down the sharp edges first by rubbing on other rocks.
Edit: also encountered the bug net over the vent getting somewhat blocked by condensation droplets. And it froze by morning.
Edit2: yes we should have had a sponge. Maybe it could double as the foam bar that is often used to prop open upper vents, hey???
my $.02 for Ron. Wishing him lots of joy, it's got to be a tough job, and transition, hiring people etc. But living the Dream!