You should definately fit a catch can, and not a cheapy from ebay because they don't have a baffle and are essentially useless. Also I don't think you really want a "breather" on a catch can other than a pressure relief valve. Normally being routed before the turbo the crankcase breather is under vacuum
I have the Flashlube Catchcan Pro, it was $229 from supersheap, it has 19mm fittings (you need to find some 16-19mm connectors) and a filter that should be replaced every 20,000kms, the genuine filter is about $90 although an aftermarket filter is about $35. I've caught about 400ml of oil in about 9000kms.
The Provent 200 is another popular one which I think has 25mm fittings. The HPD one doesn't perform well as it uses steel wool for the baffle which doesn't condense a lot of oil.
ARE is a good place to look for all things regarding intercoolers
https://www.are.com.au/Inter/topMountIntercoolers.htm