Cool Max, nice to see the use of grouping rather than variables.
I like the presets, they have interesting names. :p

There is one thing I recommend modifying. For the on input event, instead of

if (/* iswm $1-) { $1- | halt }

, I'd recommend using

if (/ !isin $left($1-,1)) && (!$ctrlenter) {

This not only checks if the slash is used, but also if the Ctrl key is held or not.

I'd also check to see if the active channel has channel mode +c is set or not. So adding to the modified code posted above, I think you should add

(c !isincs $chan(#).mode)