One example is the
This one function is 300 lines of code!
If the tasks involved with the function were broken into smaller functions that could be overridden, then extending this plugin would be a breeze... However, if you want to extend the month output and alter it just a little bit, you have to re-write 300 lines of code. It would be great if some of these functions were smaller so they could be extended without such a headache.
I see theme functions in there which is great, but sometimes when building a module that extends a module, using the theme layer just doesn't cut it.
Take it or leave it I'm just throwing it out there.