[contravariant]

You can use Jupytext and basically get the best of both worlds (it hooks into jupyterlab to save/restore a markdown version of the notebook). A possible downside is that it doesn't store the outputs of the cells, though that is intended as a feature.

And since rMarkdown just uses pandoc under the hood, it's a bit unfair to say it has better export options than ipynb which is also supported by pandoc.