Ideally, I'd like all pistols to be 100% accurate. just nerf firing rate on Pretty Boy's and I think the Winger could be left how it is after the accuracy add (because I don't see how adding accuracy will make the Winger any better, but then again I'm a beginner so yeah nerf the hypothetical new winger if it will need it).
I also think adding spray is a terrible idea for TF2. Automatic weapons are already a stretch as it is. The hitscan weapons are supposed to elevate aim above all else, not to mention sprays are the territory of army sims and 'realistic'-esque shooters. Maaaybe a simple recoil where you have to pull down but even that sounds against the spirit of TF2.
I ( in my beginner noobiness ) think that as long as the damage is low and the fire rate is low enough, a spray would not be needed to balance a 100% accurate pistol.