Which Bios Settings To Leave On

I picked up a Gigabyte J4005N D2P and have been playing around with it. Unsurprisingly it had very high latency out of the box. The bios is pretty limited in what can be turned off. I turned off vt-d, c states, eist, and all power savings. This didn't do much to help me out. I was experiencing 60-100k on the servo thread.
I went ahead and modded the bios to give me access to all the settings the manufacturer has access too. I turned off everything just as a baseline. Now my max jitter on my servo thread is at 25000 with isolcpus=1,2,3 (without isolcpus set I was around 50000).

This is using Stretch. I tried Mint and uspace but I was still around 50000-60000

I'm using a Mesa 5i25 so I'm not too worried about 25000. But I am curious if there are settings I should turn back on? Most of the tuning tips I have seen involve turning things off.

I'm going to give Wheezy a try as soon I can get it too boot, right now it is giving me a panic until I figure out what I need to turn back on.

IMHO, you are better off to leave the isolcpus setting off and live with somewhat worse latency than to throw most of the system performance away. 60000 ns latency is basically meaningless with a 1 KHZ servo thread.

If it bothers you you can use a configuration with the DPLL and get the sampling latency down to 250 ns or so, even with 300 usec of host latency

on ETH use everything below 100000ns is quite good to go for
as special if you got Steppers in use
even hybrids will fit this numbers
only some concern on servos can be issued but on low encoder pulses 1000/r will speed a servo drive over 12m/min at 0,005mm/step