Speed up spawning and Python on HPC

Dear Batchspawner developers/users,

this is not an issue, just asking for best practices/advices.
Technically, our Jupyterhub (1.1.0) deployment on HPC using batchspwner (1.0.0) works fine. However, there are still some drawbacks that reduce the use of the server.

1. Spawning notebooks is taking so long even if computing nodes already affected to the Slurm job
2. Loading/importing python packages is very slow

Anyone facing this problem? is there a way to speed up those processes on HPC?

For information, we use modules for python packages and also jupyterhub-singleuser is located in a conda env.

Thank you in advance.