One thing CloudCostTree already handles: a local apply-time policy gate
Most teams I talked to don't have a CI/CD pipeline checking cost or governance policy before terraform apply, they just run it locally. That's what guard is for: cloudcosttree guard -- terraform apply.
To be clear, this isn't a simulation, it's your real terraform apply. guard never runs one on its own, it only wraps the exact command you were already going to run, checks the plan against your policies, then applies that same saved plan, so there's no gap between what got checked and what got deployed.
Default behavior is warn-only, it prints violations but still applies. --block opts into actually stopping the apply on a real violation. A false positive blocking a real deploy is worse than one showing up in a report, so blocking is never the default.