great review , it's awesome . No need whatsoever to buy the Pro version if you're only using it for photography. I've been using the cheaper XP-PEN entry level pen tablets ( Star G430S/ G640 ) for ages and have also used the pro versions ( Deco Pro : https://www.xp-pen.com/product/432.html ) on occasions and there's no real difference if you're just using it for general retouching.
What the pro versions offer over the entry level ones is that they offer a lot more and finer levels of pen pressure & tilt function . If you're using it to actually draw then that's a big advantage but if you just use it as a glorified mouse then you might as well get the cheap ones.
Also, I would strongly advise to consider the Deco Pro Small versions for the same reason. A bigger tablet is better if you're doing long pen strokes but if you're just using it for retouching and as a a mouse then the smaller real estate is actually an advantage since your hand doesn't have to travel that far.