Currently it is very easy to setup and use Bumblebee on NVidia Optimus enabled notebook systems using mhwd.
Setting up bumblebee through Arch is a bit of a complicated chore, but mhwd abstracts a lot of that complexity within Manjaro, and the result is reliable, stable and easy to setup nvidia hybrid graphics configuration.
Bumblebee always uses the intel gpu by default, and allows switching to the nvidia gpu through optirun and primusrun. There is no option within bumblebee to change the default gpu from intel to nvidia, this is where PRIME comes into its own, by allowing the default gpu to be set to the discrete gpu.
This can be done manually in Manjaro, but it is a rather complicated procedure. A modification to mhwd to abstract the installation and configuration of PRIME in a similar way to bumblebee abstraction seems like a logical extension to current functionality.
PRIME is the default setup within Ubuntu, and it works very well, would be fantastic to offer this in Manjaro through mhwd.
sudo mhwd -i pci nvidia-prime
sudo mhwd -r pci nvidia-prime
sudo mhwd -i pci nouveau-prime
sudo mhwd -r pci nouveau-prime
There have been a number of threads discussing this recently, for example
Interest and demand for mhwd PRIME functionality is definitely there, so instead of adding to the discussion I think a Feature Request for this extension to mhwd is probably warranted.
If you are also interested in this, like this post, and share your thoughts on Manjaro Nvidia PRIME here.