You mean something like this?
Code:
alias blah.cmd1 { ... }
alias blah.cmd2 { ... }
alias blah.cmd3 { ... }

becoming

Code:
alias -s blah.* {
  if ($1 == cmd1) { ... }
  if ($1 == cmd2) { ... }
  if ($1 == cmd3) { ... }
}


If I'm understanding you correctly it seems to be at best no better than the current way, and at worst very very inefficient.