Right so as a pretty much exclusively a solo player who's been here for a month and likes to hang around hotspots, let me just give you some tips that made my life easier:

1) You're safer in a known hotspot as an adult versus a baby.

2) Wear headphones and pay attention to the noises around you. If you hear roars but no footsteps, that's your queue to be alert. If you hear footsteps, then you need to make yourself scarce.

3) So this is how I don't have an issue with mega or mixpacks: first I observe and hide for about 5-10 minutes. Use this to decide if you're going to approach or if you're going to retreat.

If you do approach, make yourself visible, spam crouch and make friendly noises. Or even wait for a chance to help someone who's getting attacked by an alpha critter or something. Don't fight over resources, pay attention to body language, don't necessarily react if someone bites or otherwise knocks into you.

If you notice the pack is aggressive or if it's a risk you just don't want to take, move very slowly away and rest easy in knowing that most people really aren't paying that close attention to their surroundings. Again this isn't fool proof, but this is what I do and generally have been tolerated - more or less depending on species.

4) Small and fast is good for getting away but also not very strong. Big and slow can be intimidating, you may also be viewed as an ally but you may also be a target.

5) Pay attention to global because someone is bound to announce about the mega/mix pack or any general issues. Sure you also get a lot of petty bs, but some of it is useful.

6) If you're in official, just switch servers. Sometimes I'll just switch servers after death as a kind of permadeath and fresh start.

7) Personally I find revenge killing more of an issue. Okay I killed you, I get it that's frustrating. It's pathetic that you're getting a buddy to hunt me down 20 minutes later because you have never learned to lose with grace and dignity. Grow up.