The area around Everglades City is more more interesting than Shark Valley. Shark Valley is nice, but there isn't much there. One big paved trail that has a tram and bicycle people on it, and a couple of small foot trails.
However if you visit it on a very dry part of a very dry season (not an el Nino year) you can see a lot of wildlife.
Winter through April or May is usually dry.
The Everglades is a river a couple of inches deep and about 50 miles wide. Since it is so shallow, the sawgrass grows through the grass, hence the name "River Of Grass".
There are small islands in the river (hammocks) with hardwood trees like Mahogany and Live Oak along with pines, poisonwood, vines, and mammals, and deeper channels called sloughs (sounds like slew).
During the dry season, the river dries up except for the sloughs. Shark Valley is one of the deeper sloughs. So the fish are concentrated in teh sloughs, the birds come to feed on the fish, the mammals need the fresh water, so wildlife viewing is good.
In wet years and the summer wet season, the fish and wildlife that was concentrated in the slough now have 50 miles to spread out over, and they do.
I'll try to find some pictures later but I'm being called for lunch
