My cat was an indoor cat for his first two years but is allowed out now, with the weather we've had his window open until late and it's the only time he goes out! We give him supper at 10ish and he comes home for that and I lock the window but I think he would prefer to be out.
He lounges about the house through the day as it's noisy outside (understandable) but has access outside if he wants it.
I live in a cul-de-sac that's very quiet at night, and the closest road is quiet at night too but he tends to go the opposite direction.
I'm not sure why it makes me so nervous, maybe because I can't keep an eye on him and worry that he will go too far and get lost as he's only ever been as far as the gardens nearby.