Liability coverage, whether it's for injuries to others outside your car or damages to property (not your car), should be high enough to cover a big-ish claim. Personally, my auto policy has liability limits of: $300k per person, $500k per occurrence for bodily injury, and $100k for property damage. I also pay for an umbrella policy to provide an additional $1MM per occurrence. So I'm pretty well covered if I cause severe injuries or death to someone. That said, I can also dream up a scenario where I cause $10MM in injuries and my $1.5MM doesn't cover it. But that's an edge case. Liability doesn't matter much what car you drive. Your potential for causing an accident is basically the same.
PIP, UM, Med Pay, all that is for you and your passengers, regardless of fault in the accident. If you're satisfied with your own health coverage, and are aware of the gaps, then you can honestly pick whatever makes you comfortable here. Keep in mind that healthcare doesn't cover lost wages, etc, which may also be something you'd want covered in an accident. But again, it's dependent on how you want to be covered. I carry $10k per person, which for my family is fine and will cover a family OOP max deductible, and I have disability insurance provided by work. I also carry $300k/500k UM, but it doesn't cost much on my policy and I'm too lazy to lower it or get rid of it.
Comprehensive/Collision covers the Scion itself, and is completely up to you, but figure out roughly what your car is worth, versus the premium the insurance company wants to charge you and go from there. At some point, the value of your car makes it not worth the coverage in most cases.
Any other coverage, just ask yourself: if something happens, do I want this covered? If yes, then ask yourself if the premium they're charging for the coverage is worth it.
