Kubernetes "packaging" for environment do update and delete all in one batch for branch based environments?

Question

Using Kubernetes we make use of Helm and Kustomize to bundle our application. This helps consistently updating something like an application, but gets kind of bloated for a hole “environment” or cluster.

ArgoCD seems like a good solution for updating a hole cluster, as you can “mirror” your git state to the cluster. This works even when dropping resources or updating an existing complex deployment.

Now I want to build branch based ephemeral environments and think ArgoCD seems a bit bloated for this feature as for every branch environment I would have to commit to the git repository and add something.

The idea is, every branch based environment lives in its own namespace. I search for a tool managing this namespace and being able to do updates, and drops of the hole thing.

What is a good solution for this problem?