I would make covering up sex trafficking and accepting foreign bribes as President (or other elected official) punishable by firing squad.
If your pet harms someone else—you catch the punishment. They destroy someone's property? You destroyed their property. They bit someone? You bit them. They kill someone? You killed them. And you're charged appropriately. It makes no sense for you to suffer far weaker consequences just because "your property" committed those acts, vs you doing so yourself. All it breeds is complacency when it comes to owning dangerous animals. How many of these problems could be solved if people were genuinely being held accountable?
If someone falsely accuses someone else of a crime—that person is then charged with committing that crime. This would immediately greatly reduce false accusations, and what would be the downside? None that I can think of.
Poaching should be punishable by 6-12 months in jail and a 10 year loss of hunting license.
Ransomware attacks should be met with life in prison (I don't know what the actual punishment is, but it's probably not harsh enough).
Unintentionally starting wildfires should be 10 years in prison. Intentionally should be life in prison, or death penalty.
As far as crimes that I think are treated too seriously? Well at least Federally, and I'm sure in many states still, weed is treated far more seriously than it should be. It's way less dangerous than alcohol and should be treated as such. I don't know enough about other drugs to comment on them.