hi, I recently moved from Manjaro to Garuda Linux. What a big improvement.
With regards to your black screen after suspend wake. I had a similar issue on one of the 2 amd laptops I had. I've read many ideas for a solution like revert to older kernel.
In my situation I had to do the following:
- add kernel flags "amd_iommu=on iommu=pt" in order to get rid of the amdgpu errors after wake up, but this did not resolve my issue
- move from xorg display manager to wayland. Check this forum how to do it. And my issue was resolved.
Good luck!
Hope your issue is similar to mine