What's the worst thing that could happen in Honor Mode?

After 2 years and 600 hours in Tactical Mode, I'd like to try Honor Mode. Since I work and only have a few hours a week, the thing that scares me the most would be playing dozens of hours and throwing them away, dying like an idiot because my team was mind-controlled or charmed/lured or someone threw me into lava or some legendary action or something like that.

Now, what's my plan: I'd like to write down a team that's idiot-proof and prank-proof. For example: I know that with Fey Ancestry I gain advantage against being charmed or with Mindless Rage, while frenzied I cannot be charmed or frightened. I gave two examples of passives, but I think I made myself clear.

In short, I'd like to list:

1. What are the worst things, worst statuses, or worst unexpected events that can happen to you in Honor Mode?

2. What are the classes, races, equipment, and tactics that can prevent the worst things?

3. What are the most important things for the whole run (for example high initiative to begin first, having Shovel or a duergar to start battles being invisible so you can surprise enemies, always have an escape plan (invisibility potions and so on), leaving a companion to the camp so he can resurrect TPK through Withers and so on).

I don't want to play like a paranoid, but I don't want to waste my time because I have done a single silly thing. Can you help me with your ideas/experiences?

Thanks in advance.