a lot of hoses can perish but the stock clamps are a load of crap and the first suspects for leaks on the hoses. If any are leaking you can generally swap the factory stupid spring clamp for a real hose clamp and good to go.
But if you keep smelling oil and it doesn't go away, the valve covers may be leaking which isn't all that uncommon. They are of course right above the headers so you need to get down under the car and really look. This is really how long is a piece of string question because it could be a lot of things that leak, just going to have to take a flashlight and work your way through each possibility if the smell doesn't go away. It does take a while for the smell, as already said for even a small amount of oil spilled, to go away...