Without any constraint, my favourite keyboard is currently the Cherry G80-3000. That may change as it had in the past.
However, my favourite keyboard is never free from any constraint. My favourite at work is not my my favourite at home, and vice versa. At any particular time, my favourite keyboad has to satisfy: key feel, key sound, and environment tolerance to noise produced by keys. For example, if at home, I like the Customizer 104 and the Cherry G80-3000, I cannot use them at work, and therefore neither is going to be my favourite keyboard there.
At home, there are time when my favourite keyboard is a rubber dome. When my daughter is having a light sleep or on days following a migraine episode, a rubber dome is a nice to have.