I know some oil ends up in the air filter but mine's leaking it onto the pipes. Big deal?

 

Not a big deal. Clean or replace the element and check that you don't have the oil level too high. Most people keep the oil level in the middle between full & add.

 

Situation normal until you re-route the breathers which I personally recommend you do. Oil is not part of a good combustion mixture. All my bikes are routed to a single hose to the ground.

 

Yeah, as Nomadmax said, you really should consider venting to atmosphere... In addition to solving your current issue, it results in a much cleaner combustion chamber and a better combustion mixture. It's setup the way it is at the factory for emissions reasons, and for any other functional purpose. I do believe in properly controlling significant emissions, but the impact of venting externally is not significant in that respect.

There really isn't any downside to making this change, and there's plenty of upside.