I'd want to figure out where the seepage originates and the rate. If it's the head cover, no big deal...either replace the gasket, or give it the occasional wipe down. On the other hand, consider that this motor isn't stock. You are running an overbored/resleeved cylinder and high-compression piston ,with a much smaller-than-stock skirt. That gives you higher peak cylinder pressures and less gasket sealing (clamping) surface area, plus more undesirable piston movement. Pump gas quality is inconsistent and declining. You don't always get the octane shown on the pump and it wouldn't take much detonation, caused by inadequate fuel, to kill a head gasket... or rock the piston hard enough to start hammering the cylinder walls on the thrust sides. As I recall, you also changed-over to what appeared to be a less-effective air filter than what you began with. A minuscule amount of dirt can do a lot of damage in very little time.
Check the crankcase vent hose. If there's more oil drippage than there used to be, that would indicate more blowby. If it looks the same as always, then it's probably nothing more serious than a gasket going away.