The designer alan shaw tried to address some of your concern
Granted he is a salesman afterall, you may want to take it with a grain of salt
Otherwise he is helpful at elaborating his design philosophy
Good luck with your search
I was using naim uniti (amp portion from naim nait 5i i believe, so less than 50w) as my one in all setup. It was my very first taste of hifi, so the change from lofi to hifi was quite dramatic. I wasn't too educated on amp power, control, etc