The next CooldownWatch won't have item cooldowns in it. I'll likely make a separate module just for tracking item cooldowns because I very much dislike the way it's currently implemented.
How about doing it similar to Procodile, in that none of the internal cooldowns are defined initially, but rather the addon "learns" them as you use them. Sure, the cooldown displayed wouldn't be accurate the first time you use it, but after about 2 or 3 days, it's near 100% accurate. Would take a lot of the work out of having to manage and add in new internal cooldowns, as shipped with the addon.