I would love a proper deesser as well.
I´ve been using the following work around:
* Activate the Ducker on the channel you wish to deS
* Choose an unused aux send master as sidechain for the Ducker
* Send the channel you wish to deS to the previously selected aux master
* Adjust the master aux graphic eq to boost the S frequency and cut everything else
* Tweak Ducker settings to obtain the desired compression
This follows the same principle of EQ to Compressor Sidechain that large format analogue consoles have. Since update 1.9 refined the Ducker´s controls, this is now 100% efective. Can also be used to control other problematic frequency bands, such as excessive bass on electric instruments or excessive brightness on acoustic guitars.
Cheers!