I have a few ground rules that I've generally kept with my ships and they became more important with this Klingon design. The old FASA Construction Manual has a good amount of backstory detailing the history of individual Federation components but nothing of the sort for the other factions in the game. In order not to introduce powerful systems like torpedoes or engines too early in the timeline, I personally limit myself by the earliest introduction seen in the appropriate FASA Recognition Guide. For example, if the KCC cloaking device was first seen in the guide on a ship introduced on 2/12 in the Klingon Guide, I generally wouldn't put it on a ship introduced before that date. The exception that I allow myself is that I can introduce a single system one year early per ship (so on 2/11 in the example above). In the case of the D-22, the KCC cloaking device is the ship component I chose to introduce early and reflected that early inclusion in the backstory. Without further chit-chat, here is my take on the D-22 Klingon Light Cruiser.
Klingon D-22 Light Cruiser pdf
Editor's note: I initially called this ship class the D-12 as the designation was not taken in the FASAverse but I've been informed by knowledgeable fans that it's taken by no less than Star Trek movie canon for a Next Generation Bird of Prey variant! With some searching, it looks like D-22 doesn't conflict with either FASA or movie canon so I've switched it to that.