I went there 10 years ago, more peaceful. Its now more commercialised/developed. The Philae temple was impressive, perhaps you should also make a day trip to Abu Simbel. Cruising on the traditional felucca is a beautiful experience, especially for sunset. Apart from shopping at Philae Essences Palace or a few papyrus shops, we didn't find anything interesting including the local market.
Tips for other travellers
Best hotel is the Sofitel Legend Old Cataract. Movenpick resort is ok, but its on an island, via boat trasfer. Its comfortable but not luxurious.
cruising on a felucca
Coptic Christian church
Movenpick Resort Aswan