CNFS of fixed-size spool and the fact that expire is based on disk space rather than article arrival date is not a bug, but a feature. People will rather drop old articles than stopping the entire news system and fixing it manually. NFS Feeding articles via NFS is a bad idea. NNTP is much better. Traffic stats Traffic seems to double 2x every 18 months.
Traffic increases linearly with the user population increase.
Incremental article gzipping will be good for non-binary newsgroups. A few upstream and bunch of downstreams. 2-4x variance is not noticed. Multithreading nnrpd is desirable. If you had money, add as much RAM as you can.