you said it was leeking oil now right?
since the pan will need to come back off get a strait edge ruler and check the pan mounting rails and looc close to the rear and front pan lips to see if it looks warped or out of shape.

it could be that when you last installed the oil pan gasket the gasket had moved on you. and caused it to leek again.

are you overfilling it with oil?

are you alternating between tightening the pan bolts in a crisscross pattern?

if you feel that you should try a PCV valve on the engine , remember that it will only do its job of pulling air through the crankcass if you putt the PCV valve in one valve cover with out any other filters or vents for air. the pcv valve must pull air through the engine coming "in" from the other valvecover.

or you can get a crankcase evacuation pump, that is belt drivin and pulls larger amounts of air through the crankcase, to releave exsessive pressure in the bottom of the engine.
if you decide to go this route you can either buy a performance pump, or you can build one if you can make your own brackets, and use a smog pump off of a bone yard car, to serve as a pump on your car.

hope i was helpfull.