the number of alias's that one can have...  

from the list of acceptable uses of an alias....

"Use of topical humor when the alias enhances the humor"
 
"The creation of a character(literary license) to be used in an informative, fun, innocuously sarcastic, philanthropic, as well as topical way.

I used to use aliases all the time for the purpose, but now never do, though I'd love to again.

People still complain about aliases and it's bullshit.  I had about 200 of them an almost all were used for humor or to play off someone's handle.  Did I flame with some?  Sure.  But I still flame with my handle and single alias.
Look at it this way: multiple aliases were banned because TER felt the GD Board had gotten too toxic.  Did it get less toxic with only one alias?  Nope!  So what's the point?  If TER wanted to make the board less fun, then they succeeded.

My theory (as a noted non-sociologist) is that the aliases allowed for a harmless and often humorous means of accommodating the dark side and keeping it within bounds much as porn and P4P contain the darker of men's urges and prevent the more harmful products of our sex urge from becoming more prevalent.

By removing this escape route we have seen the rise of board piñatas starting with MDkiller and steadily increasing to our current bumper crop of misogynists.