There's no SMB on my home network at all, since I don't have any Windows machines to support. For file storage/access, I use NFS which works beautifully across my Macs and Linux boxes. Speeds are appropriate for a 1Gbps link. For Time Machine, it's netatalk pointed at a HFS+ volume:

    [Time Machine]
    path = /mnt/backups
    time machine = yes

This setup has been rock-solid for close to a decade, and persisted across different NAS hardware. Current NAS is a Buffalo Terastation minus it's crappy built-in software, plus a barebones Debian install.