Great Plugin by the way.
I'm trying to implement this on a site where I am excluding the majority of the categories on the blog, upwards of 15 categories in all. The glitch I ran into is that it works perfectly except when listing categories in the side column in that it doesn't look at the final record in the category list, thereby leaving in one of the excluded categories, I've tweaked it by editing the following for loop in the ace_get_terms function.
for ($i=0; $i <= $c; $i++)
for ($i=0; $i <= $c+1; $i++)
This seems to take care of it however the problem seems to stem from the fact that when an item is unset in a numerically indexed array the other items in that same array adopt different ids thereby throwing off the array index.