Hi @LaurentGoderre. Thanks so much for your inquiry.
I noticed that your question references the helm/stable repository and not the official Elastic Helm charts repo. While we have been collaborating with the community chart maintainers on migration plan for users switching from the helm/charts Elasticsearch and Kibana charts to the official Elastic charts, we don't have any direct influence on the contents of the helm/stable repository. I'm not sure whether you're already aware of this but the helm/stable Elasticsearch and Kibana charts are in the process of being deprecated. Here are the pre-deprecation notices for Elasticsearch and Kibana.
The Elastic Helm charts are configured in such a way that the various products are able to connect and work with each other out of the box. I haven't yet seen a request for a single chart which will deploy multiple products but I'd be interested to understand more about your use case. If this is something you are interested in requesting/discussing, I would recommend opening an issue in the elastic/helm-charts repo and we can explore the idea more fully there.