360 cam question

I get your point and not totally disagreeing or saying the OP should go with a big cam.
Yes bigger cams extend the upper rpm powerband and make most gains on top but they also generally add decently in the 3000-5000 rpm range also making a lot more power then stock and decently over a smaller performance cam here. So even if you spend little time over 5000 rpms your still gaining.
But it sounds like the op doesn't care about "more power' or "most gains" or "maximum" anything. He just wants a cam that works with his combo that has a "noticeable idle." Here's a 318 with a Whiplash cam. (I don't know which one) Sounds nice at idle. It probably smoothes right out at about 2000 rpm or so.