mke1

In my case roaming does not work great with high density. If that is the key feature for you then I would say yes.

I don't use virtual cell option, prefer setting up channels manually

on 5Ghz

I did not say I use virtual cell, actually I always turn it off

Yes, even more, some not enabled With your counting it should not work anyway

Not sure where did you get that and what ap and controller you are talking about but that is not true. I got way over 70 devices with one radio only and working fine with ap 320 I agree that multi channel works better for high density but it may be a problem to set ip up for somebody

If you don't want all traffic to go through the controller make dataplane mode into bridge and tag ap vlan, make sure every ap broadcasting that ssid is tagged also on the swtich. Btw even 8 Gbit of traffic does not sound like real life. Personally I turn off virtual cell since it usually does not work good with high density (depending how you define it)