There's failure and then there's failure. None of my 11+ year old cars on the lot (6 of em, all licensed and running) are completely free of oil leaks except for the '97 that had a complete short block rebuild and everything else cleaned, painted, and re-gasketed in 2006. Everything else leaks somewhere, and most in more than one place.
If my spouse's '07 Grand Marquis with 21,xxx on it starts leaking oil anytime soon, I'll call that a failure. Anything else on the other cars gets processed on a case by case basis. Sort of a triage thing. Is the leak big or small? Does whatever fluid that's leaking need to be replenished often enough to be a PITA? Does the location of the leak present a danger to the car or occupants? Does it leave evidence everywhere I go, and is it enough to be embarrassing? Etc., etc.
I can't think of anything else that might be leaking in your case. If the cam covers seem to be leaking more than you can tolerate, you might just verify that the bolts are tight first. A few things up top seem to get loose over time, especially things like valve cover bolts.
If you decide to replace the seals on those covers, the time to do it is at the same time as the intake gaskets. You gotta pull the plenum anyway, and then you can get that infernal plastic intake chamber that attaches to the throttle bodies out. That might give you reasonable access to the cam covers.
And while you're into it that far, you can check and replace inner tie rod bushings if needed, plus check the steering rack mounting bushings. Oh, and did I mention that would also be a great time to replace the heater hoses (if not all the hoses on the car) and the little 4" hose that "T"s to the back of the manifold?
But be careful listening to me.... I'll have you pulling the entire engine before you know it, and then you can *really* have some fun!