After making a few versions of NoobAI checkpoint, I finally find one that is an upgrade from the Illustrious version V2.0.
In short: Both Euler and Euler A can be used as sampler (others can be used too, but you will have to test and find out what setting work best for you)
Use Euler and low CFG scale (1.5-3) if you want realistic looking image
Use Euler/Euler A and high CFG scale (3-7) if you want 2.5/anime looking image.
(Fig.1 Difference on realism depending on CFG scale, running Euler as sampler)
If you have the time and interest to know a bit further:
Euler a
CFG scale (1.0) will give you very realistic image, like a photo, and hence you will have less flexible background, pose and lower saturation;
CFG scale 2.0 seems to be a good balance between realism and artistic for most of the cases.