Unfortunately, I'm not a big fan of the yaml-hell that crossplane is either.
But as a Terraform replacement systeminit.com is still the strongest looking contender.
Consider CDK8s (Typescript or Go) or Jsonnet. We evaluated Cue and the two aforementioned options and ended up with CDK8s using Typescript and it's incredibly powerful.
There's nothing like terraform plan/apply?
I mean - some help wrangling yaml is welcome - but I already get (some) help from terraform with the k8s provider there...
Do you check in the generated yaml in git, or just the typescript code?
https://cdk8s.io/docs/latest/get-started/typescript/
Unfortunately, I'm not a big fan of the yaml-hell that crossplane is either.
But as a Terraform replacement systeminit.com is still the strongest looking contender.