No offense to your code, Slade, however, in my opinion, running a timer every 10 seconds would be a waste of resources.
Checking the number of users upon joining, is a good idea, but once that's done, then one only needs to check after people part, quit or are kicked.
In regards to the usage of $cid, for a code like this, it's not necessary, as the checking doesn't have to be done over multiple networks.
Here's my current recommendation for a full code
on me:*:join:#:{
chkusers $chan
}
on !*:part:#:{
chkusers $chan
}
on !*:quit:{
chkusers $chan
}
on *:kick:#:{
if $knick != $me {
chkusers $chan
}
}
alias chkusers {
if $nick($1,0) == 1 {
part $1
}
}