if (%chan !isin %text) && ($me isop $chan) && ($nick !isop $chan) {
    kick %chan %nick Don't Advertise (First Warning) 

can just be

 if ($chan !isin $1-) && ($me isop $chan) && ($nick !isop $chan) {
    kick $chan $nick Don't Advertise (First Warning)

no need for the variables

i got a feeling something isnt right with your 3 levels of wanrings
looks like your using
1, 300 and 400, arent they levels of err userpower?
like with a dream bot, 1 is normal user 300 halfop and 400 op

:s that may need looking into

maybe you should set a variable with how many times they have been warned and depending on warnings increase the punishment

maybe add on website advertising aswell