I have the Lite-Touch and the XA and XA2, and it seems that comparing any of the Oly XA series to the Nikon Lite-Touch / AF600 is like comparing apples and oranges. They're both cameras, but with completely different operating characteristics.
While the Oly XA series cameras exposure control ranges from aperture priority to full auto exposure depending on the model, the focusing and film transport are manual in nature. The XA is a beautifully elegant compact rangefinder, while the rest, excepting the fixed focus XA1, are scale focus viewfinder cameras. Addressing the OP, the viewfinder is clear and easy to use on both my XA and XA2; I have no personal experience with the XA4.
On the other hand, the Nikon AF600 / Lite-Touch is a wonderful little auto everything point and shoot camera with a wide 28mm lens and available panorama mask. There are several flash modes, a self-timer and an infinity focused landscape mode which are all very useful in making the best of various shooting situations. Back to the OP, the viewfinder is not as nice as on my XA series cameras. It is a physically smaller viewfinder and as it covers the wider FOV of the 28mm lens, the viewfinder image is correspondingly less magnified then the viewfinder on the XA / XA2 cameras with their 35mm lens.
For the apples to apples aspects of these cameras. I have put film through both the XA and AF600 / Lite-Touch and am currently working on a roll in my XA2. Both cameras have delivered properly exposed , detailed, and sharply focused pictures. While I like both, IMO, I think that the XA lens has a slight edge on color reproduction.
Sorry for being so round about getting here, but I certainly think that the XA series has the better viewfinder.