Well, it's not just the grain, obviously the transfer to film was made with color changes that would occur to the animation in mind.
I really don't mind if a straight, grainless CAPS transfer is made, provided a film print is used to color correct it.
Since LD's and VHS tapes are low res formats, the grain really isn't very noticeable, since it is mushed away because of the low resolution.
Grain became really noticeable only when BD's came along to reveal all that detail, so I don't think it should be re-inserted.
I do recall, when this project was just starting, that there was a lot of video noise. Perhaps that can be attributed to the capture card, and maybe that would be a way to improve the video, using less filtering later.