Both upper and lower will probably still be a Zoo in September. Lower used to be $24, but I think it's now $48 for the photographer tour. I think the big difference is that you have to have a tripod for the photographers tour. The photographers "tour" in lower used to be you pay the money, and they give you two hours down there by yourself (unguided). Now there are two tour groups doing lower, and you have to go with a guide. Last time I went in April, it was so full of tourists, I only got to shoot about 40 minutes of the two hours. The rest of the time was spent waiting for other groups to pass, or waiting for people to get out of the frame.
There are sunbeams in both, but upper is more known for the Peter Lik style, beam hitting the floor ones. It is also narrower at the top, so is probably more subject to time of year. There are also sunbeams in Lower, but they are more likely to be hitting the walls. There is a nice one that goes through the keyhole arch in late morning.
Photographers tours in upper are only 11:00 to 1:00 if I remember correctly. Lower you can do any time of day.
Your 16-35 should be fine for the whole slot. I almost always use my 17-40, and get all the shots I want. There is not much call for Telephoto in the canyon.
For either one, you'll want a tripod. Your shots will be very limited without. I would recommend doing upper or lower antelope, but if you have more time in the area, Waterholes canyon is worth a look. Not as extensive of a narrows, but you'll have the place to yourself for $5 and a short hike.