I wouldn't upgrade the stiffness of the rear shock too much unless you are going to put stiffer springs in the front.
You don't mention what year your wing is. If you have a pre-2012, you could replace your stock shock and spring with a 2012 or newer one and the OEM spring will be 100 pounds stiffer.
The traxxion shock with 1100# spring is excellent and the 1200# progressive spring on a stock shock is ok, but as Fred stated earlier, the stock shock was really not designed to dampen a spring that large.
What you DO NOT want to do is put an 1100 or 1200 pound rear spring on and leave the weak stock OEM springs in the front. Traxxion sells front springs for $90. It would be well worth it to upgrade those as well if you upgrade the rear spring to anything bigger than OEM spec. (For reference...I believe the 2012 and newer OEM is 1000 pounds and the 2001-2010 is 900 pounds)
2016 KTM Super Duke GT
2015 Honda Grom
2015 Yamaha FZ-09
2013 Honda GL1800 ABS
2004 Suzuki GSXR 750 (Track)