It's Cobra^'s explanation that helps to understand why the bans have to be placed in specific order
Yes, it's possible, with this (slightly modified) alias:
alias extraban if $2 { var %c = $1, %n = $2 } | else var %c = #, %n = $1 | tokenize 32 5 6 8 7 9 0 1 3 2 4 | ban %c %n $*
