I posted this as a comment but thought it might be helpful to share it here as well.
I recently stumbled on a project that is in development. It’s called “Supercell WX” and it’s awesome! Currently on Pre-release 3. Includes Level 3 and Level 2 data, multi-pane views and much more. It's similar to GR2 but obviously still in the early stages. Some links below but you should definitely check it out.
Website: https://supercell-wx.readthedocs.io/en/latest/#
Discord for development discussion: https://discord.gg/S2jxNMfG (it says this link expires in 7 days?)
Github to download the program: https://github.com/dpaulat/supercell-wx/releases