Left Behind suggestion
Left Behind is a perk that does one specific thing and does it modestly well. However I see two issues: it tends to encourage an unhealthy playstyle of "waiting for your teammates to die" and it can be rendered useless by the killer closing it unless you bring a key with you in advance, which again limits your opportunities to be helpful. So I suggest the following modest change:
Once you have completed 75% progress on a gen (maybe higher?) this perk's Secondary Function activates. You may now rummage through a chest to find a guaranteed Dull Key.
This will encourage you to work with your team mates in exchange for a way out if the hatch is closed. Additionally but less important, the aura reading should maybe be upped a level to somewhere around 46 meters? I feel like by the time the aura is read you can already hear the hatch sound which makes things a little redundant.
I fully admit this was an idea I came up with on the fly so any suggestions are more than welcome!