Helen's post is excellent.
I would have been harsher with regard to NPS. I suspect if you are not comparing it to NC it is fine film, but nc has everything on NPS -- IMNSHO.
I would add the following:
All neg film is limited by the paper and the person/thing that determines colour balance. You can not stuff the wide latitude of the film on to the relatively narrow latitude of paper. Paper has its own personality as well which can be troublesome -- usually in contrast it seems.
Each film has, to a varying degree, a unique pallette. This makes them suitable for some applications (wedding, portraiture as an example), but less suitable for others. This also limits the overall acuracy. A film that does a good job with plastic colours will general not be as good with earth tones and vise versa.
The most neutral chromes tend to be older films: EPR, EPN and to a far lesser degree EPP. EPR and EPN are not blue at all. EPP leans that way but nothing like Provia.
E200 is a wonderful film that has a very wide latitude (the shadows have detail as well as the highlights), is pretty neutral, and pushes well. It also crossprocesses very well.
E100vs, s and sw are not neutral, but pretty films. They have meduim to high saturation and contrast. I have not used the G or GX yet.
Provia and Velvia are very different animals. They are not nuetral, and are also very pretty films. I have not used the newer velvia 100, but do prefer velvia over provia. Many people think these two chromes are the best available. I am not in love with the Provia 'look' it is often to cool (as in blue), and unaturally saturated.
Having said that I like Velvia because it is over the top when it comes to saturation. This comes at the expense of contrast and latitude though.
Astia is the most neutral of the Fuji films, but only when compared to Velvia and Provia. I met a portrait photographer who uses Fuji's MS pro 100-1000 chrome and says that it is the most neutral he has used when rated at 200 to 400 iso. I didn't see any examples and have never used the film.
I have also heard good things about RSX, but have never used it.