The game stutters with my 32 GB of RAM.

Here is a workaround that works for me: First, you need to setup some cgroups. This will work differently according to your OS. Here is what I did on manjaro, ymmv:

• install cgcreate (cgroup-tools on debian, libcgroup in AUR, ...)
• add cgroup_enable=memory swapaccount=1 to your kernel-arguments (consult your distro's docs on how to do this)
• on each boot you want to run this game, run the following in a terminal:

sudo cgcreate -g memory:nep
sudo 'echo 8G > /sys/fs/cgroup/nep/memory.max'
sudo chown -R $(whoami) /sys/fs/cgroup/

• Set the steam launch args to WINE_ALERT_SIMULATE_SCHED_QUANTUM=1 cgexec -g memory:nep %command%
• If you don't want the black models:
  • Using a HEX-Editor, remove the framerate limit (https://www.pcgamingwiki.com/wiki/Megadimension_Neptunia_VIIR#High_frame_rate) - I used bless - search for 41 55 55 85 41 and replace it with 41 71 1C 87 40
  • Note: this will still cap your framerate at 60 FPS, but the game will display the correct models... somehow.

Now it runs butter smooth, even with overkill hardware. Enjoy!