Generally it is a good idea to start at stock and adjust from there, we all ski different there are no magic numbers, move one at a time and then back if it doesn't work, so that you get to work out what each movement does for you.
Possibly add Length, More Tip or Binding Placement, it is possible that the tip is not engaged enough to maintain cross course direction, if that doesn't work out add depth.
You are going to have use a few sets to work it out, we all ski differently and like the ski to feel the way we like individually.
A Ski Buddy of mine, changed from his EVO to the ION 3, had some issues, after trying binding and fin tweaks he couldn't work it out until went back on his EVO, as it turned out he thought the EVO gave him a bit more speed across course.
Went back on his ION 3 with 7 Degrees wing instead of 8 Degrees, He is Happy and looking very good on it.