If we doubled numbers that would be epic.. but do we need more than that?
Don't know about the 'we', but 'I' definitely do.
When AH actually had twice the current numbers I already struggled to find battles and gameplay to my liking. I never was here for dueling.
Doubling current numbers only would mean 20-50 players at the time I can play when my lil one will be in the kindergarten, and like 100-170 during my prime time.
For comparison, we had about three times the current population back when I started in 2005, and more than four times during the heydays (with the dreaded dual LW setup, but still hardly below 100 players even during downtime).
(Disclaimer: Yes, I'm fully aware that I would never get exactly the same experience again no matter how many players because of "Been there done that")
If I were an US palyer, I would be quite happy with 'only' twice the current numbers - But I ain't and I can not play at 3 AM any longer like I often did in the past