I think quality engine oil also goes a long way. I'm using Liqui Moly at the moment. It has a low ash content.
I also run Liqui Moly Super Diesel Additive every 2km or so in a tank. There are many alternatives.
An oil catch can might be an idea too. I have all the parts but haven't got around to fitting it yet. Time!
What else? Good you had the EGR recall.
Quality fuel. Some gas stations don't switch to winter additive early. So in colder climates make sure you have a winter additive to avoid diesel gumming up the engine. I used STP last year and it lasted about 5k miles.
Keep an eye on induction hoses. Inlet/vacuum/charge pipes. I haven't heard of any failings around 100k but expect some preventive measures can be taken. Get a boost gauge if you want as it's easier to spot a boost leak that way.
Taking care of the DPF is also important. Avoid short runs and always allow a regeneration to complete.
A bit more on DPF's here: