To be honest, I haven't seen a lot of blatant elemental magic in the books I've read and I've read a fair few of them. As always I think the individual treament of the idea is what's important. When I have come across some elemental magic it's helped me to feel part of the story because this is something I have at least some exposure to and knowledge of. It all depends how geeky you want to get about it. Magic systems to me enhance a good story but aren't the story themselves. If a writer takes forever to laboriously explain to me the precepts behind the magical system I am already bored.
They are not a bad way of adding structure to an already vague system, but because it is so vague that there is also a lot of room to go wrong. I think the most important thing to consider is consistency. No matter what kind of system you set up, you should keep to it. Besides the sake of the reader, it also helps you avoid plot holes. Can you imagine how ridiculous it is for a water mage that can produce water out of nowhere to die of dehydration in a desert? However, I till prefer to keep it a bit vague to save myself the headache of doing tons of research. "Magic" should only be a supplement to the story, and it should not detract attention away from the actual story.
Even being overused, you can still find your own unique ways to add elemental magic. For example, Fullmetal Alchemist (Although in the show it's considered science.) This had a unique version of elemental magic, and very subtle restrictions it.
