GPU/NIC usage graph for settings homepage

There are already some existing suggestions addressing most of what you describe.

GPU usage

Drive usage / DiskIO

More, e.g. CPU temperature

Plex should already show network usage – though that’s only focusing on Plex’ own traffic/streaming.

I suggest you vote/comment in those existing threads.
If you feel the need to keep the NIC usage, let’s focus this suggestion on that particular feature.