Ditto to Hon-Su RE: the drag washers needing replacing, sounds weird to me. I don't think you'll find anyone on here that would reccomend 3rd party upgrades for the Stella drag, it's pretty much top of the heap straight out of the box.
The line roller bearing is something i've done once before and it needs doing again on my 10K FA so that's not too unusal - mine is about 3 years old. I've never taken it apart but assume it's not a fully sealed bearing in there, a bit of salt, water and time sitting and it will start to break it down. It's a tight little corner in there, probably not hard to leave a drop or two of water behind, even if you doing your maintenance after each trip.
Maybe ask the Shimano techs for some advice on maintenance, just to make sure your being meticulous in the right way? They are pretty but you don't want to love it to death