I hope that people aren't setting their sights too high on this, because the overall experience for the largest group of players is going to trump all else.
Honestly, as a couple of others have mentioned, the current Glide mechanic will already handle most of this by default, with the possible differences occurring if you try to land through a storm.
Normal flight after leaving Glide might hopefully have more variables, and you can rest assured that the ships that have no lift surfaces will be hand-waived, and they will not require any special module for that unless all ships require said module.
A few have mentioned Explorers - the longer they are out, the less likely they would be inclined to land in these conditions if it is indeed a truly hazardous venture. This, effectively, and over time, locks Explorers out of more and more of this content, which would be highly counter-intuitive game design. A revamp to deep space ship repair could address this to a certain extent, but at some point, when you are talking about months (or years) of Exploration data, the risk just starts to get really high. In other words, the Exploration community should not be dis-incentivized from doing their primary activity, so I just don't see atmospheric landings being much more hazardous than what currently exists.
Also, while I would like environmental hazards, none of those will actually end up being any more dangerous than current star scooping, or at worst, Neutron Cones. You might take some minor damage (that can be repaired) from storms etc., but only serious foolishness would cause you to be in any real danger. The days of people taking their lumps are rapidly fading in the past, as such, those kinds of mechanics are fading with them. There are some games that relish difficulty (Ninja Gaiden, Dark Souls, etc.), but this is not one of them, and isn't likely to become one of them.
Riôt