Solid list. Two more for a ZFS-based box: cap zfs_arc_max explicitly if idle RAM usage matters, ZFS will happily eat most of your RAM for ARC and won’t always release it cleanly, keeping memory controllers busier than needed at idle. And check hdparm -B / hd-idle for spinning drives not in constant use, letting them actually spin down makes a bigger power dent than people expect.

Good writeup. One caution from having done this on a couple boxes: test stability after flipping ASPM on, especially with NVMe drives in the mix. There is a known class of Linux kernel PCIe ASPM bugs where L1/L1.1 substates cause certain NVMe (and some USB3) controllers to drop out under load, especially on older Intel platforms. If a boot drive starts acting flaky after enabling this, ASPM is worth reverting before chasing anything else.