Yes, actually we have done more experiments with top layers than what is in the paper.
We'll post some pics later, but we now have an 'ironing' feature in IceSL and this works with curved slicing. The top layers end up being very smooth. We also have the option of changing the direction of the fill pattern on the top layer, but in the end we don't use it much.
Curved slicing is a bit more difficult and requires more tuning, but the results can be significantly better on some parts.
Best,
Sylvain