they alll seem somewhat sterile and lifeless. IMHO, they all need a tube preamp to warm them up@lou_setriodes Nelson understands the importance of lower ordered harmonics since you can't eliminate distortion altogether (this is a lot bigger topic than there might be room for on this thread!). So his stuff doesn't have that dryness to which you allude above. But a good tube preamp shouldn't be particularly warm- just neutral :)
Dreaming of a DIY 8W Class A amp designed by Nelson Pass?
I've never built one, or heard them but this kit looks fun as hell, and includes everything you need:
https://diyaudiostore.com/collections/frontpage/products/amp-camp-amp-kit?variant=7072933085218