There are a few positions I particularly like, and they all have their merits...
If she is squatting, I like the view from the front, back or side. It is still erotic even if I can't really see much.
Even better than squatting, the hovering position seen either from the side or the back shows off the lovely, athletic curves of my wife's legs and rear end. She might show me just the side if she wants to tease me, only allowing me to see her stream without having clear sight of her genitals.
To see her standing (her preferred position), seen from the front is spectacular, especially when she is going at full force. A rear view is exactly that, and is particularly arousing when she takes a sly look over her shoulder at me watching her.
In the bath, to have her squat above and facing me is one hell of a sight as she fires a torrential blast high on my chest. Perhaps the best of all is the same position but seen from the rear, giving me a stunning view of her entire underside as she lets loose a torrent.